CINXE.COM
自明群 - Wikipedia
<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="ja" dir="ltr"> <head> <meta charset="UTF-8"> <title>自明群 - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )jawikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"ja", "wgMonthNames":["","1月","2月","3月","4月","5月","6月","7月","8月","9月","10月","11月","12月"],"wgRequestId":"b5f3c4f8-5cba-436a-b926-c05a46b65514","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"自明群","wgTitle":"自明群","wgCurRevisionId":67757383,"wgRevisionId":67757383,"wgArticleId":3088559,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["有限群","群論","数学に関する記事"],"wgPageViewLanguage":"ja","wgPageContentLanguage":"ja","wgPageContentModel":"wikitext","wgRelevantPageName":"自明群","wgRelevantArticleId":3088559,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":true,"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"ja","pageLanguageDir": "ltr","pageVariantFallbacks":"ja"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":true,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":3000,"wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q568687","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.gadget.PDFLinkIcon":"ready","ext.gadget.RedirectColor":"ready","ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options" :"loading","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["site","mediawiki.page.ready","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.NormalizeCharWidth","ext.gadget.suppressEnterAtSummaryBox","ext.gadget.checkSignature","ext.gadget.charinsert","ext.gadget.WikiMiniAtlas","ext.gadget.switcher","ext.gadget.protectionIndicator","ext.urlShortener.toolbar","ext.centralauth.centralautologin","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints" ,"ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=ja&modules=ext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=ja&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=ja&modules=ext.gadget.PDFLinkIcon%2CRedirectColor&only=styles&skin=vector-2022"> <link rel="stylesheet" href="/w/load.php?lang=ja&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="自明群 - Wikipedia"> <meta property="og:type" content="website"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//ja.m.wikipedia.org/wiki/%E8%87%AA%E6%98%8E%E7%BE%A4"> <link rel="alternate" type="application/x-wiki" title="編集" href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (ja)"> <link rel="EditURI" type="application/rsd+xml" href="//ja.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://ja.wikipedia.org/wiki/%E8%87%AA%E6%98%8E%E7%BE%A4"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.ja"> <link rel="alternate" type="application/atom+xml" title="WikipediaのAtomフィード" href="/w/index.php?title=%E7%89%B9%E5%88%A5:%E6%9C%80%E8%BF%91%E3%81%AE%E6%9B%B4%E6%96%B0&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-自明群 rootpage-自明群 skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">コンテンツにスキップ</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="サイト"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="メインメニュー" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">メインメニュー</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">メインメニュー</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">サイドバーに移動</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">非表示</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> 案内 </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/%E3%83%A1%E3%82%A4%E3%83%B3%E3%83%9A%E3%83%BC%E3%82%B8" title="メインページに移動する [z]" accesskey="z"><span>メインページ</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:%E3%82%B3%E3%83%9F%E3%83%A5%E3%83%8B%E3%83%86%E3%82%A3%E3%83%BB%E3%83%9D%E3%83%BC%E3%82%BF%E3%83%AB" title="このプロジェクトについて、できること、情報を入手する場所"><span>コミュニティ・ポータル</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:%E6%9C%80%E8%BF%91%E3%81%AE%E5%87%BA%E6%9D%A5%E4%BA%8B" title="最近の出来事の背景を知る"><span>最近の出来事</span></a></li><li id="n-newpages" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E6%96%B0%E3%81%97%E3%81%84%E3%83%9A%E3%83%BC%E3%82%B8" title="最近新規に作成されたページの一覧"><span>新しいページ</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E6%9C%80%E8%BF%91%E3%81%AE%E6%9B%B4%E6%96%B0" title="このウィキにおける最近の更新の一覧 [r]" accesskey="r"><span>最近の更新</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E3%81%8A%E3%81%BE%E3%81%8B%E3%81%9B%E8%A1%A8%E7%A4%BA" title="無作為に選択されたページを読み込む [x]" accesskey="x"><span>おまかせ表示</span></a></li><li id="n-sandbox" class="mw-list-item"><a href="/wiki/Wikipedia:%E3%82%B5%E3%83%B3%E3%83%89%E3%83%9C%E3%83%83%E3%82%AF%E3%82%B9" title="練習用のページ"><span>練習用ページ</span></a></li><li id="n-commonsupload" class="mw-list-item"><a href="//commons.wikimedia.org/wiki/Special:UploadWizard?uselang=ja" title="画像やメディアファイルをウィキメディア・コモンズにアップロード"><span>アップロード (ウィキメディア・コモンズ)</span></a></li> </ul> </div> </div> <div id="p-help" class="vector-menu mw-portlet mw-portlet-help" > <div class="vector-menu-heading"> ヘルプ </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:%E7%9B%AE%E6%AC%A1" title="情報を得る場所"><span>ヘルプ</span></a></li><li id="n-villagepump" class="mw-list-item"><a href="/wiki/Wikipedia:%E4%BA%95%E6%88%B8%E7%AB%AF" title="プロジェクトについての意見交換"><span>井戸端</span></a></li><li id="n-notice" class="mw-list-item"><a href="/wiki/Wikipedia:%E3%81%8A%E7%9F%A5%E3%82%89%E3%81%9B" title="プロジェクトについてのお知らせ"><span>お知らせ</span></a></li><li id="n-bugreportspage" class="mw-list-item"><a href="/wiki/Wikipedia:%E3%83%90%E3%82%B0%E3%81%AE%E5%A0%B1%E5%91%8A" title="ウィキペディア・ソフトウェアのバグ報告"><span>バグの報告</span></a></li><li id="n-contact" class="mw-list-item"><a href="/wiki/Wikipedia:%E9%80%A3%E7%B5%A1%E5%85%88" title="ウィキペディアやウィキメディア財団に関する連絡先"><span>ウィキペディアに関するお問い合わせ</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/%E3%83%A1%E3%82%A4%E3%83%B3%E3%83%9A%E3%83%BC%E3%82%B8" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-ja.svg" style="width: 7.5em; height: 1.25em;"> <img class="mw-logo-tagline" alt="" src="/static/images/mobile/copyright/wikipedia-tagline-ja.svg" width="100" height="14" style="width: 6.25em; height: 0.875em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/%E7%89%B9%E5%88%A5:%E6%A4%9C%E7%B4%A2" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Wikipedia内を検索 [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>検索</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Wikipedia内を検索" aria-label="Wikipedia内を検索" autocapitalize="sentences" title="Wikipedia内を検索 [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="特別:検索"> </div> <button class="cdx-button cdx-search-input__end-button">検索</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="個人用ツール"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="表示"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="ページのフォントサイズ、幅、色の外観を変更する" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="表示" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">表示</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="//donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_ja.wikipedia.org&uselang=ja" class=""><span>寄付</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=%E7%89%B9%E5%88%A5:%E3%82%A2%E3%82%AB%E3%82%A6%E3%83%B3%E3%83%88%E4%BD%9C%E6%88%90&returnto=%E8%87%AA%E6%98%8E%E7%BE%A4" title="アカウントを作成してログインすることをお勧めしますが、必須ではありません" class=""><span>アカウント作成</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=%E7%89%B9%E5%88%A5:%E3%83%AD%E3%82%B0%E3%82%A4%E3%83%B3&returnto=%E8%87%AA%E6%98%8E%E7%BE%A4" title="ログインすることを推奨します。ただし、必須ではありません。 [o]" accesskey="o" class=""><span>ログイン</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="その他の操作" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="個人用ツール" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">個人用ツール</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="利用者メニュー" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="//donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_ja.wikipedia.org&uselang=ja"><span>寄付</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=%E7%89%B9%E5%88%A5:%E3%82%A2%E3%82%AB%E3%82%A6%E3%83%B3%E3%83%88%E4%BD%9C%E6%88%90&returnto=%E8%87%AA%E6%98%8E%E7%BE%A4" title="アカウントを作成してログインすることをお勧めしますが、必須ではありません"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>アカウント作成</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=%E7%89%B9%E5%88%A5:%E3%83%AD%E3%82%B0%E3%82%A4%E3%83%B3&returnto=%E8%87%AA%E6%98%8E%E7%BE%A4" title="ログインすることを推奨します。ただし、必須ではありません。 [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>ログイン</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> ログアウトした編集者のページ <a href="/wiki/Wikipedia:%E3%82%A6%E3%82%A3%E3%82%AD%E3%83%9A%E3%83%87%E3%82%A3%E3%82%A2%E3%81%B8%E3%82%88%E3%81%86%E3%81%93%E3%81%9D" aria-label="編集の詳細"><span>もっと詳しく</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E8%87%AA%E5%88%86%E3%81%AE%E6%8A%95%E7%A8%BF%E8%A8%98%E9%8C%B2" title="このIPアドレスからなされた編集の一覧 [y]" accesskey="y"><span>投稿記録</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E3%83%88%E3%83%BC%E3%82%AF%E3%83%9A%E3%83%BC%E3%82%B8" title="このIPアドレスからなされた編集についての議論 [n]" accesskey="n"><span>トーク</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"><!-- CentralNotice --></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="サイト"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="目次" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">目次</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">サイドバーに移動</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">非表示</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">ページ先頭</div> </a> </li> <li id="toc-性質" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#性質"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>性質</span> </div> </a> <ul id="toc-性質-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-関連項目" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#関連項目"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>関連項目</span> </div> </a> <ul id="toc-関連項目-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-参考文献" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#参考文献"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>参考文献</span> </div> </a> <ul id="toc-参考文献-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="目次" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="目次の表示・非表示を切り替え" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">目次の表示・非表示を切り替え</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">自明群</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="特定の記事の別の言語版に移動します。 利用可能な言語23件" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-23" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">23の言語版</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B2%D9%85%D8%B1%D8%A9_%D8%A8%D8%AF%D9%8A%D9%87%D9%8A%D8%A9" title="アラビア語: زمرة بديهية" lang="ar" hreflang="ar" data-title="زمرة بديهية" data-language-autonym="العربية" data-language-local-name="アラビア語" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Grup_trivial" title="カタロニア語: Grup trivial" lang="ca" hreflang="ca" data-title="Grup trivial" data-language-autonym="Català" data-language-local-name="カタロニア語" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Trivi%C3%A1ln%C3%AD_grupa" title="チェコ語: Triviální grupa" lang="cs" hreflang="cs" data-title="Triviální grupa" data-language-autonym="Čeština" data-language-local-name="チェコ語" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Triviel_gruppe" title="デンマーク語: Triviel gruppe" lang="da" hreflang="da" data-title="Triviel gruppe" data-language-autonym="Dansk" data-language-local-name="デンマーク語" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Triviale_Gruppe" title="ドイツ語: Triviale Gruppe" lang="de" hreflang="de" data-title="Triviale Gruppe" data-language-autonym="Deutsch" data-language-local-name="ドイツ語" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%A4%CE%B5%CF%84%CF%81%CE%B9%CE%BC%CE%BC%CE%AD%CE%BD%CE%B7_%CE%BF%CE%BC%CE%AC%CE%B4%CE%B1" title="ギリシャ語: Τετριμμένη ομάδα" lang="el" hreflang="el" data-title="Τετριμμένη ομάδα" data-language-autonym="Ελληνικά" data-language-local-name="ギリシャ語" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/Trivial_group" title="英語: Trivial group" lang="en" hreflang="en" data-title="Trivial group" data-language-autonym="English" data-language-local-name="英語" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Grupo_trivial" title="スペイン語: Grupo trivial" lang="es" hreflang="es" data-title="Grupo trivial" data-language-autonym="Español" data-language-local-name="スペイン語" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Triviaali_ryhm%C3%A4" title="フィンランド語: Triviaali ryhmä" lang="fi" hreflang="fi" data-title="Triviaali ryhmä" data-language-autonym="Suomi" data-language-local-name="フィンランド語" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Groupe_trivial" title="フランス語: Groupe trivial" lang="fr" hreflang="fr" data-title="Groupe trivial" data-language-autonym="Français" data-language-local-name="フランス語" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Trivi%C3%A1lis_csoport" title="ハンガリー語: Triviális csoport" lang="hu" hreflang="hu" data-title="Triviális csoport" data-language-autonym="Magyar" data-language-local-name="ハンガリー語" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%9E%90%EB%AA%85%EA%B5%B0" title="韓国語: 자명군" lang="ko" hreflang="ko" data-title="자명군" data-language-autonym="한국어" data-language-local-name="韓国語" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Triviale_groep" title="オランダ語: Triviale groep" lang="nl" hreflang="nl" data-title="Triviale groep" data-language-autonym="Nederlands" data-language-local-name="オランダ語" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Grupa_trywialna" title="ポーランド語: Grupa trywialna" lang="pl" hreflang="pl" data-title="Grupa trywialna" data-language-autonym="Polski" data-language-local-name="ポーランド語" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Grupo_trivial" title="ポルトガル語: Grupo trivial" lang="pt" hreflang="pt" data-title="Grupo trivial" data-language-autonym="Português" data-language-local-name="ポルトガル語" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Grup_trivial" title="ルーマニア語: Grup trivial" lang="ro" hreflang="ro" data-title="Grup trivial" data-language-autonym="Română" data-language-local-name="ルーマニア語" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A2%D1%80%D0%B8%D0%B2%D0%B8%D0%B0%D0%BB%D1%8C%D0%BD%D0%B0%D1%8F_%D0%B3%D1%80%D1%83%D0%BF%D0%BF%D0%B0" title="ロシア語: Тривиальная группа" lang="ru" hreflang="ru" data-title="Тривиальная группа" data-language-autonym="Русский" data-language-local-name="ロシア語" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Trivialna_grupa" title="スロベニア語: Trivialna grupa" lang="sl" hreflang="sl" data-title="Trivialna grupa" data-language-autonym="Slovenščina" data-language-local-name="スロベニア語" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Trivialgrupp" title="スウェーデン語: Trivialgrupp" lang="sv" hreflang="sv" data-title="Trivialgrupp" data-language-autonym="Svenska" data-language-local-name="スウェーデン語" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%8E%E0%AE%B3%E0%AE%BF%E0%AE%AF_%E0%AE%95%E0%AF%81%E0%AE%B2%E0%AE%AE%E0%AF%8D" title="タミル語: எளிய குலம்" lang="ta" hreflang="ta" data-title="எளிய குலம்" data-language-autonym="தமிழ்" data-language-local-name="タミル語" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A2%D1%80%D0%B8%D0%B2%D1%96%D0%B0%D0%BB%D1%8C%D0%BD%D0%B0_%D0%B3%D1%80%D1%83%D0%BF%D0%B0" title="ウクライナ語: Тривіальна група" lang="uk" hreflang="uk" data-title="Тривіальна група" data-language-autonym="Українська" data-language-local-name="ウクライナ語" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E7%95%B6%E7%84%B6%E7%BE%A4" title="中国語: 當然群" lang="zh" hreflang="zh" data-title="當然群" data-language-autonym="中文" data-language-local-name="中国語" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E5%B9%B3%E5%87%A1%E7%BE%A3" title="広東語: 平凡羣" lang="yue" hreflang="yue" data-title="平凡羣" data-language-autonym="粵語" data-language-local-name="広東語" class="interlanguage-link-target"><span>粵語</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q568687#sitelinks-wikipedia" title="言語間リンクを編集" class="wbc-editpage">リンクを編集</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="名前空間"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/%E8%87%AA%E6%98%8E%E7%BE%A4" title="本文を閲覧 [c]" accesskey="c"><span>ページ</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/%E3%83%8E%E3%83%BC%E3%83%88:%E8%87%AA%E6%98%8E%E7%BE%A4" rel="discussion" title="本文ページについての議論 [t]" accesskey="t"><span>ノート</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="別の言語に切り替える" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">日本語</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="表示"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/%E8%87%AA%E6%98%8E%E7%BE%A4"><span>閲覧</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=edit" title="このページのソースコードを編集する [e]" accesskey="e"><span>編集</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=history" title="このページの過去の版 [h]" accesskey="h"><span>履歴表示</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="ページツール"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="ツール" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">ツール</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">ツール</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">サイドバーに移動</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">非表示</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="その他の操作" > <div class="vector-menu-heading"> 操作 </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/%E8%87%AA%E6%98%8E%E7%BE%A4"><span>閲覧</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=edit" title="このページのソースコードを編集する [e]" accesskey="e"><span>編集</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=history"><span>履歴表示</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> 全般 </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E3%83%AA%E3%83%B3%E3%82%AF%E5%85%83/%E8%87%AA%E6%98%8E%E7%BE%A4" title="ここにリンクしている全ウィキページの一覧 [j]" accesskey="j"><span>リンク元</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E9%96%A2%E9%80%A3%E3%83%9A%E3%83%BC%E3%82%B8%E3%81%AE%E6%9B%B4%E6%96%B0%E7%8A%B6%E6%B3%81/%E8%87%AA%E6%98%8E%E7%BE%A4" rel="nofollow" title="このページからリンクしているページの最近の更新 [k]" accesskey="k"><span>関連ページの更新状況</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:%E3%83%95%E3%82%A1%E3%82%A4%E3%83%AB%E3%81%AE%E3%82%A2%E3%83%83%E3%83%97%E3%83%AD%E3%83%BC%E3%83%89" title="ファイルをアップロードする [u]" accesskey="u"><span>ファイルをアップロード</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/%E7%89%B9%E5%88%A5:%E7%89%B9%E5%88%A5%E3%83%9A%E3%83%BC%E3%82%B8%E4%B8%80%E8%A6%A7" title="特別ページの一覧 [q]" accesskey="q"><span>特別ページ</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&oldid=67757383" title="このページのこの版への固定リンク"><span>この版への固定リンク</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=info" title="このページについての詳細情報"><span>ページ情報</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=%E7%89%B9%E5%88%A5:%E3%81%93%E3%81%AE%E3%83%9A%E3%83%BC%E3%82%B8%E3%82%92%E5%BC%95%E7%94%A8&page=%E8%87%AA%E6%98%8E%E7%BE%A4&id=67757383&wpFormIdentifier=titleform" title="このページの引用方法"><span>このページを引用</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=%E7%89%B9%E5%88%A5:UrlShortener&url=https%3A%2F%2Fja.wikipedia.org%2Fwiki%2F%25E8%2587%25AA%25E6%2598%258E%25E7%25BE%25A4"><span>短縮URLを取得する</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=%E7%89%B9%E5%88%A5:QrCode&url=https%3A%2F%2Fja.wikipedia.org%2Fwiki%2F%25E8%2587%25AA%25E6%2598%258E%25E7%25BE%25A4"><span>QRコードをダウンロード</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> 印刷/書き出し </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-create_a_book" class="mw-list-item"><a href="/w/index.php?title=%E7%89%B9%E5%88%A5:%E3%83%96%E3%83%83%E3%82%AF&bookcmd=book_creator&referer=%E8%87%AA%E6%98%8E%E7%BE%A4"><span>ブックの新規作成</span></a></li><li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=%E7%89%B9%E5%88%A5:DownloadAsPdf&page=%E8%87%AA%E6%98%8E%E7%BE%A4&action=show-download-screen"><span>PDF 形式でダウンロード</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&printable=yes" title="このページの印刷用ページ [p]" accesskey="p"><span>印刷用バージョン</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> 他のプロジェクト </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q568687" title="関連付けられたデータリポジトリ項目へのリンク [g]" accesskey="g"><span>ウィキデータ項目</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="ページツール"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="表示"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">表示</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">サイドバーに移動</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">非表示</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">出典: フリー百科事典『ウィキペディア(Wikipedia)』</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="ja" dir="ltr"><p><a href="/wiki/%E6%95%B0%E5%AD%A6" title="数学">数学</a>において、<b>自明群</b>、<b>自明な群</b> (trivial group)、<b>単位群</b> はただ1つの元からなる<a href="/wiki/%E7%BE%A4_(%E6%95%B0%E5%AD%A6)" title="群 (数学)">群</a>である。すべてのそのような群は<a href="/wiki/%E5%90%8C%E5%9E%8B" class="mw-redirect" title="同型">同型</a>であるので、英語などではしばしば定冠詞をつけて <i>the</i> trivial group などと呼ばれる。自明群のただ1つの元は<a href="/wiki/%E5%8D%98%E4%BD%8D%E5%85%83" title="単位元">単位元</a>であるので普通 0, 1, <i>e</i> のように文脈に応じて表記される。群の演算が ∗ であれば <span lang="en" class="texhtml"><i>e</i> ∗ <i>e</i> = <i>e</i></span> によって定義される。 </p><p>同様に定義される<b>自明モノイド</b> (trivial monoid) もまた群である。その唯一の元がそれ自身の逆元でありしたがって自明群と同じであるからである。 </p><p>自明群を<a href="/wiki/%E7%A9%BA%E9%9B%86%E5%90%88" title="空集合">空集合</a>と混同してはならない。(これは元を全くもたず、単位元を欠くため、群にはなりえない。) </p><p>任意の群 <i>G</i> が与えられると、単位元のみからなる部分集合は、それ自身が自明群である <i>G</i> の<a href="/wiki/%E9%83%A8%E5%88%86%E7%BE%A4" title="部分群">部分群</a>であり、<i>G</i> の<b>自明な部分群</b> (trivial subgroup) と呼ばれる。また、<i>G</i> 自身も明らかに <i>G</i> の部分群であるので、<i>G</i> も自明な部分群と呼ばれることがあるが、これは著者によって異なるので注意が必要である。群によってはこれら以外にも自明に部分群になるものがあるが、それらは自明な部分群とは呼ばれない。 </p><p>"<i>G</i> は非自明な真の部分群をもたない" (<i>G</i> has no nontrivial proper subgroups) という言い回しが意味するのは、<i>G</i> のすべての部分群は自明群 {<i>e</i>} および群 <i>G</i> 自身であるということである。 </p> <div class="mw-heading mw-heading2"><h2 id="性質"><span id=".E6.80.A7.E8.B3.AA"></span>性質</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=edit&section=1" title="節を編集: 性質"><span>編集</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>自明群は<a href="/wiki/%E4%BD%8D%E6%95%B0_(%E7%BE%A4%E8%AB%96)" title="位数 (群論)">位数</a> 1 の<a href="/wiki/%E5%B7%A1%E5%9B%9E%E7%BE%A4" title="巡回群">巡回群</a>である。そのようなものとして自明群は Z<sub>1</sub> あるいは C<sub>1</sub> と書ける。群の演算が和であれば、自明群は通常単に 0 と表記される。群演算が積であれば 1 が自明群の表記となる。 </p><p>群の自明な部分群(および群自身)は<a href="/wiki/%E6%AD%A3%E8%A6%8F%E9%83%A8%E5%88%86%E7%BE%A4" title="正規部分群">正規部分群</a>である。正規部分群が自明な部分群と群自身しかないような非自明な群は<a href="/wiki/%E5%8D%98%E7%B4%94%E7%BE%A4" title="単純群">単純群</a>と呼ばれる。 </p><p>自明群は<a href="/wiki/%E7%BE%A4%E3%81%AE%E5%9C%8F" title="群の圏">群の圏</a>において<a href="/wiki/%E9%9B%B6%E5%AF%BE%E8%B1%A1" class="mw-redirect" title="零対象">零対象</a>として振る舞う。つまり、それは<a href="/wiki/%E5%A7%8B%E5%AF%BE%E8%B1%A1" class="mw-redirect" title="始対象">始対象</a>かつ<a href="/wiki/%E7%B5%82%E5%AF%BE%E8%B1%A1" class="mw-redirect" title="終対象">終対象</a>である。 </p> <div class="mw-heading mw-heading2"><h2 id="関連項目"><span id=".E9.96.A2.E9.80.A3.E9.A0.85.E7.9B.AE"></span>関連項目</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=edit&section=2" title="節を編集: 関連項目"><span>編集</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><span title="リンク先の項目はまだありません。新規の執筆や他言語版からの翻訳が望まれます。"><a href="/w/index.php?title=%E5%B0%8F%E3%81%95%E3%81%84%E7%BE%A4%E3%81%AE%E4%B8%80%E8%A6%A7&action=edit&redlink=1" class="new" title="「小さい群の一覧」 (存在しないページ)">小さい群の一覧</a><span style="font-size: 0.77em; font-weight: normal;" class="noprint">(<a href="https://en.wikipedia.org/wiki/List_of_small_groups" class="extiw" title="en:List of small groups">英語版</a>)</span></span></li></ul> <div class="mw-heading mw-heading2"><h2 id="参考文献"><span id=".E5.8F.82.E8.80.83.E6.96.87.E7.8C.AE"></span>参考文献</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&action=edit&section=3" title="節を編集: 参考文献"><span>編集</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><span class="citation mathworld" id="Reference-Mathworld-Trivial_Group"><style data-mw-deduplicate="TemplateStyles:r101121245">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation.cs-ja1 q,.mw-parser-output .citation.cs-ja2 q{quotes:"「""」""『""』"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free a,.mw-parser-output .citation .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited a,.mw-parser-output .id-lock-registration a,.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription a,.mw-parser-output .citation .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:var(--color-success,#3a3);margin-left:0.3em}.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}</style><cite id="CITEREFRowland,_Todd_and_Weisstein,_Eric_W." class="citation web cs1 cs1-prop-foreign-lang-source">Rowland, Todd and Weisstein, Eric W. <a rel="nofollow" class="external text" href="https://mathworld.wolfram.com/TrivialGroup.html">"Trivial Group"</a>. <i>mathworld.wolfram.com</i> (英語).</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=mathworld.wolfram.com&rft.atitle=Trivial+Group&rft.au=Rowland%2C+Todd+and+Weisstein%2C+Eric+W.&rft_id=https%3A%2F%2Fmathworld.wolfram.com%2FTrivialGroup.html&rfr_id=info%3Asid%2Fja.wikipedia.org%3A%E8%87%AA%E6%98%8E%E7%BE%A4" class="Z3988"></span></span></li> <li><cite style="font-style:normal" class="citation book">森田康夫『代数概論』裳華房、1987年。<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r101121245"><a href="/wiki/ISBN" title="ISBN">ISBN</a> <a href="/wiki/%E7%89%B9%E5%88%A5:%E6%96%87%E7%8C%AE%E8%B3%87%E6%96%99/978-4-7853-1311-1" title="特別:文献資料/978-4-7853-1311-1">978-4-7853-1311-1</a>。</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=%E4%BB%A3%E6%95%B0%E6%A6%82%E8%AB%96&rft.aulast=%E6%A3%AE%E7%94%B0%E5%BA%B7%E5%A4%AB&rft.au=%E6%A3%AE%E7%94%B0%E5%BA%B7%E5%A4%AB&rft.date=1987&rft.pub=%E8%A3%B3%E8%8F%AF%E6%88%BF&rft.isbn=978-4-7853-1311-1&rfr_id=info:sid/ja.wikipedia.org:%E8%87%AA%E6%98%8E%E7%BE%A4"><span style="display: none;"> </span></span></li></ul> <!-- NewPP limit report Parsed by mw‐web.codfw.main‐78fc6dc798‐5nvvt Cached time: 20241121040208 Cache expiry: 2592000 Reduced expiry: false Complications: [] CPU time usage: 0.130 seconds Real time usage: 0.176 seconds Preprocessor visited node count: 1311/1000000 Post‐expand include size: 7708/2097152 bytes Template argument size: 1132/2097152 bytes Highest expansion depth: 20/100 Expensive parser function count: 1/500 Unstrip recursion depth: 0/20 Unstrip post‐expand size: 3578/5000000 bytes Lua time usage: 0.059/10.000 seconds Lua memory usage: 2887766/52428800 bytes Number of Wikibase entities loaded: 0/400 --> <!-- Transclusion expansion time report (%,ms,calls,template) 100.00% 160.859 1 -total 47.76% 76.826 1 Template:MathWorld 45.54% 73.251 1 Template:Cite_web2 37.75% 60.721 1 Template:Cite_book 35.36% 56.882 1 Template:Citation/core-ja-jp 21.44% 34.495 1 Template:Citation/identifier 20.31% 32.666 1 Template:ISBN2 12.79% 20.571 1 Template:仮リンク 7.91% 12.728 1 Template:Catalog_lookup_link 6.64% 10.685 1 Template:Error-small --> <!-- Saved in parser cache with key jawiki:pcache:idhash:3088559-0!canonical and timestamp 20241121040208 and revision id 67757383. Rendering was triggered because: page-view --> </div><!--esi <esi:include src="/esitest-fa8a495983347898/content" /> --><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">「<a dir="ltr" href="https://ja.wikipedia.org/w/index.php?title=自明群&oldid=67757383">https://ja.wikipedia.org/w/index.php?title=自明群&oldid=67757383</a>」から取得</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/%E7%89%B9%E5%88%A5:%E3%82%AB%E3%83%86%E3%82%B4%E3%83%AA" title="特別:カテゴリ">カテゴリ</a>: <ul><li><a href="/wiki/Category:%E6%9C%89%E9%99%90%E7%BE%A4" title="Category:有限群">有限群</a></li><li><a href="/wiki/Category:%E7%BE%A4%E8%AB%96" title="Category:群論">群論</a></li><li><a href="/wiki/Category:%E6%95%B0%E5%AD%A6%E3%81%AB%E9%96%A2%E3%81%99%E3%82%8B%E8%A8%98%E4%BA%8B" title="Category:数学に関する記事">数学に関する記事</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> 最終更新 2018年3月17日 (土) 10:59 (日時は<a href="/wiki/%E7%89%B9%E5%88%A5:%E5%80%8B%E4%BA%BA%E8%A8%AD%E5%AE%9A#mw-prefsection-rendering" title="特別:個人設定">個人設定</a>で未設定ならば<a href="/wiki/%E5%8D%94%E5%AE%9A%E4%B8%96%E7%95%8C%E6%99%82" title="協定世界時">UTC</a>)。</li> <li id="footer-info-copyright">テキストは<a rel="nofollow" class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.ja">クリエイティブ・コモンズ 表示-継承ライセンス</a>のもとで利用できます。追加の条件が適用される場合があります。詳細については<a class="external text" href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use">利用規約</a>を参照してください。</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy/ja">プライバシー・ポリシー</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:%E3%82%A6%E3%82%A3%E3%82%AD%E3%83%9A%E3%83%87%E3%82%A3%E3%82%A2%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6">ウィキペディアについて</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:%E5%85%8D%E8%B2%AC%E4%BA%8B%E9%A0%85">免責事項</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">行動規範</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">開発者</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/ja.wikipedia.org">統計</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookieに関する声明</a></li> <li id="footer-places-mobileview"><a href="//ja.m.wikipedia.org/w/index.php?title=%E8%87%AA%E6%98%8E%E7%BE%A4&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">モバイルビュー</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-f69cdc8f6-rf9q5","wgBackendResponseTime":155,"wgPageParseReport":{"limitreport":{"cputime":"0.130","walltime":"0.176","ppvisitednodes":{"value":1311,"limit":1000000},"postexpandincludesize":{"value":7708,"limit":2097152},"templateargumentsize":{"value":1132,"limit":2097152},"expansiondepth":{"value":20,"limit":100},"expensivefunctioncount":{"value":1,"limit":500},"unstrip-depth":{"value":0,"limit":20},"unstrip-size":{"value":3578,"limit":5000000},"entityaccesscount":{"value":0,"limit":400},"timingprofile":["100.00% 160.859 1 -total"," 47.76% 76.826 1 Template:MathWorld"," 45.54% 73.251 1 Template:Cite_web2"," 37.75% 60.721 1 Template:Cite_book"," 35.36% 56.882 1 Template:Citation/core-ja-jp"," 21.44% 34.495 1 Template:Citation/identifier"," 20.31% 32.666 1 Template:ISBN2"," 12.79% 20.571 1 Template:仮リンク"," 7.91% 12.728 1 Template:Catalog_lookup_link"," 6.64% 10.685 1 Template:Error-small"]},"scribunto":{"limitreport-timeusage":{"value":"0.059","limit":"10.000"},"limitreport-memusage":{"value":2887766,"limit":52428800}},"cachereport":{"origin":"mw-web.codfw.main-78fc6dc798-5nvvt","timestamp":"20241121040208","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"\u81ea\u660e\u7fa4","url":"https:\/\/ja.wikipedia.org\/wiki\/%E8%87%AA%E6%98%8E%E7%BE%A4","sameAs":"http:\/\/www.wikidata.org\/entity\/Q568687","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q568687","author":{"@type":"Organization","name":"\u30a6\u30a3\u30ad\u30e1\u30c7\u30a3\u30a2\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3078\u306e\u8ca2\u732e\u8005"},"publisher":{"@type":"Organization","name":"\u30a6\u30a3\u30ad\u30e1\u30c7\u30a3\u30a2\u8ca1\u56e3","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2014-11-11T14:02:51Z","dateModified":"2018-03-17T10:59:15Z"}</script> </body> </html>