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Tilgængelig på 72 sprog" > <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-72" 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">72 sprog</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/%D9%85%D8%AC%D9%85%D9%88%D8%B9%D8%A9_%D8%AE%D8%A7%D9%84%D9%8A%D8%A9" title="مجموعة خالية – arabisk" lang="ar" hreflang="ar" data-title="مجموعة خالية" data-language-autonym="العربية" data-language-local-name="arabisk" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Conxuntu_vac%C3%ADu" title="Conxuntu vacíu – asturisk" lang="ast" hreflang="ast" data-title="Conxuntu vacíu" data-language-autonym="Asturianu" data-language-local-name="asturisk" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Bo%C5%9F_%C3%A7oxluq" title="Boş çoxluq – aserbajdsjansk" lang="az" hreflang="az" data-title="Boş çoxluq" data-language-autonym="Azərbaycanca" data-language-local-name="aserbajdsjansk" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-ba mw-list-item"><a href="https://ba.wikipedia.org/wiki/%D0%91%D1%83%D1%88_%D0%BA%D2%AF%D0%BC%D3%99%D0%BA%D0%BB%D0%B5%D0%BA" title="Буш күмәклек – bashkir" lang="ba" hreflang="ba" data-title="Буш күмәклек" data-language-autonym="Башҡортса" data-language-local-name="bashkir" class="interlanguage-link-target"><span>Башҡортса</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9F%D1%83%D1%81%D1%82%D0%BE%D0%B5_%D0%BC%D0%BD%D0%BE%D1%81%D1%82%D0%B2%D0%B0" title="Пустое мноства – belarusisk" lang="be" hreflang="be" data-title="Пустое мноства" data-language-autonym="Беларуская" data-language-local-name="belarusisk" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%9F%D1%83%D1%81%D1%82%D0%BE%D0%B5_%D0%BC%D0%BD%D0%BE%D1%81%D1%82%D0%B2%D0%B0" title="Пустое мноства – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Пустое мноства" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9F%D1%80%D0%B0%D0%B7%D0%BD%D0%BE_%D0%BC%D0%BD%D0%BE%D0%B6%D0%B5%D1%81%D1%82%D0%B2%D0%BE" title="Празно множество – bulgarsk" lang="bg" hreflang="bg" data-title="Празно множество" data-language-autonym="Български" data-language-local-name="bulgarsk" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Prazan_skup" title="Prazan skup – bosnisk" lang="bs" hreflang="bs" data-title="Prazan skup" data-language-autonym="Bosanski" data-language-local-name="bosnisk" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Conjunt_buit" title="Conjunt buit – catalansk" lang="ca" hreflang="ca" data-title="Conjunt buit" data-language-autonym="Català" data-language-local-name="catalansk" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%DA%A9%DB%86%D9%85%DB%95%DA%B5%DB%95%DB%8C_%D8%A8%DB%95%D8%AA%D8%A7%DA%B5" title="کۆمەڵەی بەتاڵ – sorani" lang="ckb" hreflang="ckb" data-title="کۆمەڵەی بەتاڵ" data-language-autonym="کوردی" data-language-local-name="sorani" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Pr%C3%A1zdn%C3%A1_mno%C5%BEina" title="Prázdná množina – tjekkisk" lang="cs" hreflang="cs" data-title="Prázdná množina" data-language-autonym="Čeština" data-language-local-name="tjekkisk" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%9F%D1%83%D1%88%C4%83_%D0%B9%D1%8B%D1%88" title="Пушă йыш – tjuvasjisk" lang="cv" hreflang="cv" data-title="Пушă йыш" data-language-autonym="Чӑвашла" data-language-local-name="tjuvasjisk" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Leere_Menge" title="Leere Menge – tysk" lang="de" hreflang="de" data-title="Leere Menge" data-language-autonym="Deutsch" data-language-local-name="tysk" 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%9A%CE%B5%CE%BD%CF%8C_%CF%83%CF%8D%CE%BD%CE%BF%CE%BB%CE%BF" title="Κενό σύνολο – græsk" lang="el" hreflang="el" data-title="Κενό σύνολο" data-language-autonym="Ελληνικά" data-language-local-name="græsk" 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/Empty_set" title="Empty set – engelsk" lang="en" hreflang="en" data-title="Empty set" data-language-autonym="English" data-language-local-name="engelsk" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Malplena_aro" title="Malplena aro – esperanto" lang="eo" hreflang="eo" data-title="Malplena aro" data-language-autonym="Esperanto" data-language-local-name="esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Conjunto_vac%C3%ADo" title="Conjunto vacío – spansk" lang="es" hreflang="es" data-title="Conjunto vacío" data-language-autonym="Español" data-language-local-name="spansk" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/T%C3%BChi_hulk" title="Tühi hulk – estisk" lang="et" hreflang="et" data-title="Tühi hulk" data-language-autonym="Eesti" data-language-local-name="estisk" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Multzo_huts" title="Multzo huts – baskisk" lang="eu" hreflang="eu" data-title="Multzo huts" data-language-autonym="Euskara" data-language-local-name="baskisk" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%85%D8%AC%D9%85%D9%88%D8%B9%D9%87_%D8%AA%D9%87%DB%8C" title="مجموعه تهی – persisk" lang="fa" hreflang="fa" data-title="مجموعه تهی" data-language-autonym="فارسی" data-language-local-name="persisk" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Tyhj%C3%A4_joukko" title="Tyhjä joukko – finsk" lang="fi" hreflang="fi" data-title="Tyhjä joukko" data-language-autonym="Suomi" data-language-local-name="finsk" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-fiu-vro mw-list-item"><a href="https://fiu-vro.wikipedia.org/wiki/T%C3%BChi_hulk" title="Tühi hulk – Võro" lang="vro" hreflang="vro" data-title="Tühi hulk" data-language-autonym="Võro" data-language-local-name="Võro" class="interlanguage-link-target"><span>Võro</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Ensemble_vide" title="Ensemble vide – fransk" lang="fr" hreflang="fr" data-title="Ensemble vide" data-language-autonym="Français" data-language-local-name="fransk" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Conxunto_baleiro" title="Conxunto baleiro – galicisk" lang="gl" hreflang="gl" data-title="Conxunto baleiro" data-language-autonym="Galego" data-language-local-name="galicisk" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%94%D7%A7%D7%91%D7%95%D7%A6%D7%94_%D7%94%D7%A8%D7%99%D7%A7%D7%94" title="הקבוצה הריקה – hebraisk" lang="he" hreflang="he" data-title="הקבוצה הריקה" data-language-autonym="עברית" data-language-local-name="hebraisk" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%B0%E0%A4%BF%E0%A4%95%E0%A5%8D%E0%A4%A4_%E0%A4%B8%E0%A4%AE%E0%A5%81%E0%A4%9A%E0%A5%8D%E0%A4%9A%E0%A4%AF" title="रिक्त समुच्चय – hindi" lang="hi" hreflang="hi" data-title="रिक्त समुच्चय" data-language-autonym="हिन्दी" data-language-local-name="hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Prazni_skup" title="Prazni skup – kroatisk" lang="hr" hreflang="hr" data-title="Prazni skup" data-language-autonym="Hrvatski" data-language-local-name="kroatisk" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/%C3%9Cres_halmaz" title="Üres halmaz – ungarsk" lang="hu" hreflang="hu" data-title="Üres halmaz" data-language-autonym="Magyar" data-language-local-name="ungarsk" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%B4%D5%A1%D5%BF%D5%A1%D6%80%D5%AF_%D5%A2%D5%A1%D5%A6%D5%B4%D5%B8%D6%82%D5%A9%D5%B5%D5%B8%D6%82%D5%B6" title="Դատարկ բազմություն – armensk" lang="hy" hreflang="hy" data-title="Դատարկ բազմություն" data-language-autonym="Հայերեն" data-language-local-name="armensk" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Himpunan_kosong" title="Himpunan kosong – indonesisk" lang="id" hreflang="id" data-title="Himpunan kosong" data-language-autonym="Bahasa Indonesia" data-language-local-name="indonesisk" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/T%C3%B3mamengi" title="Tómamengi – islandsk" lang="is" hreflang="is" data-title="Tómamengi" data-language-autonym="Íslenska" data-language-local-name="islandsk" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Insieme_vuoto" title="Insieme vuoto – italiensk" lang="it" hreflang="it" data-title="Insieme vuoto" data-language-autonym="Italiano" data-language-local-name="italiensk" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E7%A9%BA%E9%9B%86%E5%90%88" title="空集合 – japansk" lang="ja" hreflang="ja" data-title="空集合" data-language-autonym="日本語" data-language-local-name="japansk" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%AA%E1%83%90%E1%83%A0%E1%83%98%E1%83%94%E1%83%9A%E1%83%98_%E1%83%A1%E1%83%98%E1%83%9B%E1%83%A0%E1%83%90%E1%83%95%E1%83%9A%E1%83%94" title="ცარიელი სიმრავლე – georgisk" lang="ka" hreflang="ka" data-title="ცარიელი სიმრავლე" data-language-autonym="ქართული" data-language-local-name="georgisk" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%91%D0%BE%D1%81_%D0%B6%D0%B8%D1%8B%D0%BD" title="Бос жиын – kasakhisk" lang="kk" hreflang="kk" data-title="Бос жиын" data-language-autonym="Қазақша" data-language-local-name="kasakhisk" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EA%B3%B5%EC%A7%91%ED%95%A9" title="공집합 – koreansk" lang="ko" hreflang="ko" data-title="공집합" data-language-autonym="한국어" data-language-local-name="koreansk" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-ku mw-list-item"><a href="https://ku.wikipedia.org/wiki/Koma_vala" title="Koma vala – kurdisk" lang="ku" hreflang="ku" data-title="Koma vala" data-language-autonym="Kurdî" data-language-local-name="kurdisk" class="interlanguage-link-target"><span>Kurdî</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Copia_vacua" title="Copia vacua – latin" lang="la" hreflang="la" data-title="Copia vacua" data-language-autonym="Latina" data-language-local-name="latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lmo mw-list-item"><a href="https://lmo.wikipedia.org/wiki/Insema_voeud" title="Insema voeud – Lombard" lang="lmo" hreflang="lmo" data-title="Insema voeud" data-language-autonym="Lombard" data-language-local-name="Lombard" class="interlanguage-link-target"><span>Lombard</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Tu%C5%A1%C4%8Dia_aib%C4%97" title="Tuščia aibė – litauisk" lang="lt" hreflang="lt" data-title="Tuščia aibė" data-language-autonym="Lietuvių" data-language-local-name="litauisk" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Tuk%C5%A1a_kopa" title="Tukša kopa – lettisk" lang="lv" hreflang="lv" data-title="Tukša kopa" data-language-autonym="Latviešu" data-language-local-name="lettisk" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9F%D1%80%D0%B0%D0%B7%D0%BD%D0%BE_%D0%BC%D0%BD%D0%BE%D0%B6%D0%B5%D1%81%D1%82%D0%B2%D0%BE" title="Празно множество – makedonsk" lang="mk" hreflang="mk" data-title="Празно множество" data-language-autonym="Македонски" data-language-local-name="makedonsk" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%B6%E0%B5%82%E0%B4%A8%E0%B5%8D%E0%B4%AF%E0%B4%97%E0%B4%A3%E0%B4%82" title="ശൂന്യഗണം – malayalam" lang="ml" hreflang="ml" data-title="ശൂന്യഗണം" data-language-autonym="മലയാളം" data-language-local-name="malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%A5%D0%BE%D0%BE%D1%81%D0%BE%D0%BD_%D0%BE%D0%BB%D0%BE%D0%BD%D0%BB%D0%BE%D0%B3" title="Хоосон олонлог – mongolsk" lang="mn" hreflang="mn" data-title="Хоосон олонлог" data-language-autonym="Монгол" data-language-local-name="mongolsk" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Set_kosong" title="Set kosong – malajisk" lang="ms" hreflang="ms" data-title="Set kosong" data-language-autonym="Bahasa Melayu" data-language-local-name="malajisk" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Lege_verzameling" title="Lege verzameling – nederlandsk" lang="nl" hreflang="nl" data-title="Lege verzameling" data-language-autonym="Nederlands" data-language-local-name="nederlandsk" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Den_tomme_mengda" title="Den tomme mengda – nynorsk" lang="nn" hreflang="nn" data-title="Den tomme mengda" data-language-autonym="Norsk nynorsk" data-language-local-name="nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Den_tomme_mengden" title="Den tomme mengden – bokmål" lang="nb" hreflang="nb" data-title="Den tomme mengden" data-language-autonym="Norsk bokmål" data-language-local-name="bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Zbi%C3%B3r_pusty" title="Zbiór pusty – polsk" lang="pl" hreflang="pl" data-title="Zbiór pusty" data-language-autonym="Polski" data-language-local-name="polsk" 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/Conjunto_vazio" title="Conjunto vazio – portugisisk" lang="pt" hreflang="pt" data-title="Conjunto vazio" data-language-autonym="Português" data-language-local-name="portugisisk" 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/Mul%C8%9Bime_vid%C4%83" title="Mulțime vidă – rumænsk" lang="ro" hreflang="ro" data-title="Mulțime vidă" data-language-autonym="Română" data-language-local-name="rumænsk" 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%9F%D1%83%D1%81%D1%82%D0%BE%D0%B5_%D0%BC%D0%BD%D0%BE%D0%B6%D0%B5%D1%81%D1%82%D0%B2%D0%BE" title="Пустое множество – russisk" lang="ru" hreflang="ru" data-title="Пустое множество" data-language-autonym="Русский" data-language-local-name="russisk" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-scn mw-list-item"><a href="https://scn.wikipedia.org/wiki/Nzemi_vacanti" title="Nzemi vacanti – siciliansk" lang="scn" hreflang="scn" data-title="Nzemi vacanti" data-language-autonym="Sicilianu" data-language-local-name="siciliansk" class="interlanguage-link-target"><span>Sicilianu</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Prazan_skup" title="Prazan skup – serbokroatisk" lang="sh" hreflang="sh" data-title="Prazan skup" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="serbokroatisk" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Empty_set" title="Empty set – Simple English" lang="en-simple" hreflang="en-simple" data-title="Empty set" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Pr%C3%A1zdna_mno%C5%BEina" title="Prázdna množina – slovakisk" lang="sk" hreflang="sk" data-title="Prázdna množina" data-language-autonym="Slovenčina" data-language-local-name="slovakisk" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Prazna_mno%C5%BEica" title="Prazna množica – slovensk" lang="sl" hreflang="sl" data-title="Prazna množica" data-language-autonym="Slovenščina" data-language-local-name="slovensk" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Bashk%C3%ABsia_boshe" title="Bashkësia boshe – albansk" lang="sq" hreflang="sq" data-title="Bashkësia boshe" data-language-autonym="Shqip" data-language-local-name="albansk" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9F%D1%80%D0%B0%D0%B7%D0%B0%D0%BD_%D1%81%D0%BA%D1%83%D0%BF" title="Празан скуп – serbisk" lang="sr" hreflang="sr" data-title="Празан скуп" data-language-autonym="Српски / srpski" data-language-local-name="serbisk" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Tomma_m%C3%A4ngden" title="Tomma mängden – svensk" lang="sv" hreflang="sv" data-title="Tomma mängden" data-language-autonym="Svenska" data-language-local-name="svensk" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-szl mw-list-item"><a href="https://szl.wikipedia.org/wiki/Pusto_mynga" title="Pusto mynga – Silesian" lang="szl" hreflang="szl" data-title="Pusto mynga" data-language-autonym="Ślůnski" data-language-local-name="Silesian" class="interlanguage-link-target"><span>Ślůnski</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%B5%E0%AF%86%E0%AE%B1%E0%AF%8D%E0%AE%B1%E0%AF%81%E0%AE%95%E0%AF%8D_%E0%AE%95%E0%AE%A3%E0%AE%AE%E0%AF%8D" title="வெற்றுக் கணம் – tamil" lang="ta" hreflang="ta" data-title="வெற்றுக் கணம்" data-language-autonym="தமிழ்" data-language-local-name="tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B9%80%E0%B8%8B%E0%B8%95%E0%B8%A7%E0%B9%88%E0%B8%B2%E0%B8%87" title="เซตว่าง – thai" lang="th" hreflang="th" data-title="เซตว่าง" data-language-autonym="ไทย" data-language-local-name="thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Bo%C5%9F_k%C3%BCme" title="Boş küme – tyrkisk" lang="tr" hreflang="tr" data-title="Boş küme" data-language-autonym="Türkçe" data-language-local-name="tyrkisk" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-tt mw-list-item"><a href="https://tt.wikipedia.org/wiki/%D0%91%D1%83%D1%88_%D0%BA%D2%AF%D0%BF%D0%BB%D0%B5%D0%BA" title="Буш күплек – tatarisk" lang="tt" hreflang="tt" data-title="Буш күплек" data-language-autonym="Татарча / tatarça" data-language-local-name="tatarisk" class="interlanguage-link-target"><span>Татарча / tatarça</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9F%D0%BE%D1%80%D0%BE%D0%B6%D0%BD%D1%8F_%D0%BC%D0%BD%D0%BE%D0%B6%D0%B8%D0%BD%D0%B0" title="Порожня множина – ukrainsk" lang="uk" hreflang="uk" data-title="Порожня множина" data-language-autonym="Українська" data-language-local-name="ukrainsk" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/T%E1%BA%ADp_h%E1%BB%A3p_r%E1%BB%97ng" title="Tập hợp rỗng – vietnamesisk" lang="vi" hreflang="vi" data-title="Tập hợp rỗng" data-language-autonym="Tiếng Việt" data-language-local-name="vietnamesisk" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-vls mw-list-item"><a href="https://vls.wikipedia.org/wiki/Lege_verzoamelienge" title="Lege verzoamelienge – West Flemish" lang="vls" hreflang="vls" data-title="Lege verzoamelienge" data-language-autonym="West-Vlams" data-language-local-name="West Flemish" class="interlanguage-link-target"><span>West-Vlams</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E7%A9%BA%E9%9B%86" title="空集 – wu-kinesisk" lang="wuu" hreflang="wuu" data-title="空集" data-language-autonym="吴语" data-language-local-name="wu-kinesisk" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E7%A9%BA%E9%9B%86" title="空集 – kinesisk" lang="zh" hreflang="zh" data-title="空集" data-language-autonym="中文" data-language-local-name="kinesisk" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-zh-classical mw-list-item"><a href="https://zh-classical.wikipedia.org/wiki/%E7%A9%BA%E9%9B%86" title="空集 – Literary Chinese" lang="lzh" hreflang="lzh" data-title="空集" data-language-autonym="文言" data-language-local-name="Literary Chinese" class="interlanguage-link-target"><span>文言</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E7%A9%BA%E9%9B%86" title="空集 – kantonesisk" lang="yue" hreflang="yue" data-title="空集" data-language-autonym="粵語" data-language-local-name="kantonesisk" 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/Q226183#sitelinks-wikipedia" title="Redigér sproglinks" class="wbc-editpage">Redigér links</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="Navnerum"> <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/Tomme_m%C3%A6ngde" title="Se indholdssiden [c]" accesskey="c"><span>Artikel</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Diskussion:Tomme_m%C3%A6ngde" rel="discussion" title="Diskussion om indholdet på siden [t]" accesskey="t"><span>Diskussion</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="Ændr sprogvariant" > <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">dansk</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="Visninger"> <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/Tomme_m%C3%A6ngde"><span>Læs</span></a></li><li id="ca-ve-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Tomme_m%C3%A6ngde&veaction=edit" title="Redigér denne side [v]" accesskey="v"><span>Redigér</span></a></li><li id="ca-edit" class="collapsible vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Tomme_m%C3%A6ngde&action=edit" title="Rediger kildekoden for denne side [e]" accesskey="e"><span>Rediger kildekode</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Tomme_m%C3%A6ngde&action=history" title="Tidligere versioner af denne side [h]" accesskey="h"><span>Se historik</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Sideværktøjer"> <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="Værktøjer" > <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">Værktøjer</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">Værktøjer</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">flyt til sidebjælken</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">skjul</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="Flere muligheder" > <div class="vector-menu-heading"> Handlinger </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/Tomme_m%C3%A6ngde"><span>Læs</span></a></li><li id="ca-more-ve-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Tomme_m%C3%A6ngde&veaction=edit" title="Redigér denne side [v]" accesskey="v"><span>Redigér</span></a></li><li id="ca-more-edit" class="collapsible vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Tomme_m%C3%A6ngde&action=edit" title="Rediger kildekoden for denne side [e]" accesskey="e"><span>Rediger kildekode</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Tomme_m%C3%A6ngde&action=history"><span>Se historik</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div 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href="/wiki/Kardinalitet" title="Kardinalitet">kardinalitet</a> er nul. </p><p>Den tomme mængde skrives ⦰<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>, Ø, <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \emptyset }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi mathvariant="normal">∅</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \emptyset }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6af50205f42bb2ec3c666b7b847d2c7f96e464c7" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.505ex; width:1.162ex; height:2.509ex;" alt="{\displaystyle \emptyset }"></span> eller {}. Traditionen med at bruge symbolet <a href="/wiki/%C3%98_(bogstav)" title="Ø (bogstav)">Ø</a> som betegnelse for denne mængde skyldes <a href="/w/index.php?title=Nicolas_Bourbaki&action=edit&redlink=1" class="new" title="Nicolas Bourbaki (ikke skrevet endnu)">Nicolas Bourbaki</a> (kollektivt pseudonym for en gruppe matematikere, også kaldet Bourbaki-gruppen), der var inspireret af det skandinaviske bogstav <a href="/wiki/%C3%98_(bogstav)" title="Ø (bogstav)">Ø</a>. <sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> . </p><p>I fortiden var "0" ofte brugt som symbol for en tom mængde, men dette anses nu for at være en ukorrekt.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Referencer">Referencer</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Tomme_m%C3%A6ngde&veaction=edit&section=1" title="Redigér afsnit: Referencer" class="mw-editsection-visualeditor"><span>redigér</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Tomme_m%C3%A6ngde&action=edit&section=1" title="Edit section's source code: Referencer"><span>rediger kildetekst</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r11780210">.mw-parser-output .reflist{font-size:90%;margin-bottom:0.5em;list-style-type:decimal}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><a href="#cite_ref-1">^</a></span> <span class="reference-text">Nina Grønnum (2005, 2013) <i>Fonetik og Fonologi: Almen og dansk.</i> Akademisk forlag, København.</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">^</a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://jeff560.tripod.com/set.html">Earliest Uses of Symbols of Set Theory and Logic.</a></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><a href="#cite_ref-3">^</a></span> <span class="reference-text"><a href="/wiki/Internationalt_Standardbognummer" title="Internationalt Standardbognummer">ISBN</a> <a href="/wiki/Speciel:ISBN-s%C3%B8gning/007054235X" title="Speciel:ISBN-søgning/007054235X">007054235X</a></span> </li> </ol></div></div> <div style="clear:both; visibility:false; display:none"></div><table class="" style="width: 100%; float: none; margin: 0 auto; border-collapse: collapse; background: #FBFBFB; border: 1px solid #aaa; border-left: 10px solid #66bb77;padding: 0.25em 0.5em;"> <tbody><tr><td style="padding: 0.25em 0.5em;"><span class="metadata"><span typeof="mw:File"><a href="/wiki/Fil:Greek_lc_pi_icon.svg" class="mw-file-description" title="Matematik"><img alt="Matematik" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Greek_lc_pi_icon.svg/28px-Greek_lc_pi_icon.svg.png" decoding="async" width="28" height="27" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Greek_lc_pi_icon.svg/42px-Greek_lc_pi_icon.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Greek_lc_pi_icon.svg/56px-Greek_lc_pi_icon.svg.png 2x" data-file-width="100" data-file-height="96" /></a></span></span></td><td style="width:100%"><b>Spire</b><br /><div style="font-size:85%;line-height:135%;">Denne artikel om <a href="/wiki/Matematik" title="Matematik">matematik</a> er en <a href="/wiki/Hj%C3%A6lp:Stub" title="Hjælp:Stub">spire</a> som bør udbygges. 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