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mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%AE%E0%A7%8D%E0%A6%AF%E0%A6%BE%E0%A6%A5%E0%A6%93%E0%A6%AF%E0%A6%BC%E0%A6%BE%E0%A6%B0%E0%A7%8D%E0%A6%B2%E0%A7%8D%E0%A6%A1" title="ম্যাথওয়ার্ল্ড – Bangla" lang="bn" hreflang="bn" data-title="ম্যাথওয়ার্ল্ড" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/MathWorld" title="MathWorld – Bulgarian" lang="bg" hreflang="bg" data-title="MathWorld" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/MathWorld" title="MathWorld – Catalan" lang="ca" hreflang="ca" data-title="MathWorld" data-language-autonym="Català" data-language-local-name="Catalan" 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/MathWorld" title="MathWorld – Czech" lang="cs" hreflang="cs" data-title="MathWorld" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/MathWorld" title="MathWorld – German" lang="de" hreflang="de" data-title="MathWorld" data-language-autonym="Deutsch" data-language-local-name="German" 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/MathWorld" title="MathWorld – Greek" lang="el" hreflang="el" data-title="MathWorld" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/MathWorld" title="MathWorld – Spanish" lang="es" hreflang="es" data-title="MathWorld" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/MathWorld" title="MathWorld – Esperanto" lang="eo" hreflang="eo" data-title="MathWorld" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/MathWorld" title="MathWorld – Basque" lang="eu" hreflang="eu" data-title="MathWorld" data-language-autonym="Euskara" data-language-local-name="Basque" 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%AB%E2%80%8C%D9%88%D8%B1%D9%84%D8%AF" title="مث‌ورلد – Persian" lang="fa" hreflang="fa" data-title="مث‌ورلد" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/MathWorld" title="MathWorld – French" lang="fr" hreflang="fr" data-title="MathWorld" data-language-autonym="Français" data-language-local-name="French" 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/MathWorld" title="MathWorld – Galician" lang="gl" hreflang="gl" data-title="MathWorld" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%A7%A4%EC%8A%A4%EC%9B%94%EB%93%9C" title="매스월드 – Korean" lang="ko" hreflang="ko" data-title="매스월드" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%AE%E0%A5%88%E0%A4%A5%E0%A4%B5%E0%A4%B0%E0%A5%8D%E0%A4%B2%E0%A5%8D%E0%A4%A1" title="मैथवर्ल्ड – Hindi" lang="hi" hreflang="hi" data-title="मैथवर्ल्ड" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/MathWorld" title="MathWorld – Indonesian" lang="id" hreflang="id" data-title="MathWorld" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/MathWorld" title="MathWorld – Italian" lang="it" hreflang="it" data-title="MathWorld" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/MathWorld" title="MathWorld – Hebrew" lang="he" hreflang="he" data-title="MathWorld" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/MathWorld" title="MathWorld – Hungarian" lang="hu" hreflang="hu" data-title="MathWorld" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/MathWorld" title="MathWorld – Macedonian" lang="mk" hreflang="mk" data-title="MathWorld" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/MathWorld" title="MathWorld – Malay" lang="ms" hreflang="ms" data-title="MathWorld" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" 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/MathWorld" title="MathWorld – Dutch" lang="nl" hreflang="nl" data-title="MathWorld" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/MathWorld" title="MathWorld – Japanese" lang="ja" hreflang="ja" data-title="MathWorld" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/MathWorld" title="MathWorld – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="MathWorld" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian 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/MathWorld" title="MathWorld – Polish" lang="pl" hreflang="pl" data-title="MathWorld" data-language-autonym="Polski" data-language-local-name="Polish" 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/MathWorld" title="MathWorld – Portuguese" lang="pt" hreflang="pt" data-title="MathWorld" data-language-autonym="Português" data-language-local-name="Portuguese" 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/MathWorld" title="MathWorld – Romanian" lang="ro" hreflang="ro" data-title="MathWorld" data-language-autonym="Română" data-language-local-name="Romanian" 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/MathWorld" title="MathWorld – Russian" lang="ru" hreflang="ru" data-title="MathWorld" data-language-autonym="Русский" data-language-local-name="Russian" 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/MathWorld" title="MathWorld – Slovenian" lang="sl" hreflang="sl" data-title="MathWorld" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D9%85%D8%A7%D8%AA%D9%88%DB%86%D8%B1%DA%B5%D8%AF" title="ماتوۆرڵد – Central Kurdish" lang="ckb" hreflang="ckb" data-title="ماتوۆرڵد" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-su mw-list-item"><a href="https://su.wikipedia.org/wiki/MathWorld" title="MathWorld – Sundanese" lang="su" hreflang="su" data-title="MathWorld" data-language-autonym="Sunda" data-language-local-name="Sundanese" class="interlanguage-link-target"><span>Sunda</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Mathworld" title="Mathworld – Swedish" lang="sv" hreflang="sv" data-title="Mathworld" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B9%81%E0%B8%A1%E0%B8%97%E0%B9%80%E0%B8%A7%E0%B8%B4%E0%B8%A5%E0%B8%94%E0%B9%8C" title="แมทเวิลด์ – Thai" lang="th" hreflang="th" data-title="แมทเวิลด์" 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/MathWorld" title="MathWorld – Turkish" lang="tr" hreflang="tr" data-title="MathWorld" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/MathWorld" title="MathWorld – Ukrainian" lang="uk" hreflang="uk" data-title="MathWorld" data-language-autonym="Українська" data-language-local-name="Ukrainian" 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/MathWorld" title="MathWorld – Vietnamese" lang="vi" hreflang="vi" data-title="MathWorld" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/MathWorld" title="MathWorld – Chinese" lang="zh" hreflang="zh" data-title="MathWorld" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</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/Q719112#sitelinks-wikipedia" title="Edit 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href="https://www.google.com/search?as_eq=wikipedia&q=%22MathWorld%22">"MathWorld"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22MathWorld%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22MathWorld%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22MathWorld%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22MathWorld%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22MathWorld%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">July 2017</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p class="mw-empty-elt"> </p> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vcard"><caption class="infobox-title fn org"><i>MathWorld</i></caption><tbody><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:MathWorld_logo.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/2/2b/MathWorld_logo.png/220px-MathWorld_logo.png" decoding="async" width="220" height="35" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/2/2b/MathWorld_logo.png 1.5x" data-file-width="249" data-file-height="40" /></a></span></td></tr><tr><th scope="row" class="infobox-label">Type of business</th><td class="infobox-data category"><a href="/wiki/Privately_held_company" title="Privately held company">Private</a></td></tr><tr><th scope="row" class="infobox-label"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Type of site</div></th><td class="infobox-data"><a href="/wiki/Internet_encyclopedia_project" class="mw-redirect" title="Internet encyclopedia project">Internet encyclopedia project</a></td></tr><tr><th scope="row" class="infobox-label">Available in</th><td class="infobox-data"><a href="/wiki/English_language" title="English language">English</a></td></tr><tr><th scope="row" class="infobox-label">Owner</th><td class="infobox-data"><a href="/wiki/Wolfram_Research,_Inc." class="mw-redirect" title="Wolfram Research, Inc.">Wolfram Research, Inc.</a></td></tr><tr><th scope="row" class="infobox-label">Created by</th><td class="infobox-data"><a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Eric W. Weisstein</a><sup id="cite_ref-Making_1-0" class="reference"><a href="#cite_note-Making-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label">URL</th><td class="infobox-data url"><span class="url"><a rel="nofollow" class="external text" href="https://mathworld.wolfram.com">mathworld<wbr />.wolfram<wbr />.com</a></span> <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q719112#P856" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></td></tr><tr><th scope="row" class="infobox-label">Launched</th><td class="infobox-data">November 1999<span class="noprint">; 25 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">1999-11</span>)</span></td></tr><tr><th scope="row" class="infobox-label">Current status</th><td class="infobox-data category">Active</td></tr></tbody></table> <p><i><b>MathWorld</b></i> is an online <a href="/wiki/Mathematics" title="Mathematics">mathematics</a> reference work, created and largely written by <a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Eric W. Weisstein</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><sup id="cite_ref-:0_3-0" class="reference"><a href="#cite_note-:0-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> It is sponsored by and licensed to <a href="/wiki/Wolfram_Research,_Inc." class="mw-redirect" title="Wolfram Research, Inc.">Wolfram Research, Inc.</a> and was partially funded by the <a href="/wiki/National_Science_Foundation" title="National Science Foundation">National Science Foundation</a>'s <a href="/wiki/National_Science_Digital_Library" title="National Science Digital Library">National Science Digital Library</a> grant to the <a href="/wiki/University_of_Illinois_at_Urbana%E2%80%93Champaign" class="mw-redirect" title="University of Illinois at Urbana–Champaign">University of Illinois at Urbana–Champaign</a>.<sup id="cite_ref-:0_3-1" class="reference"><a href="#cite_note-:0-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Eric W. Weisstein</a>, the creator of the site, was a <a href="/wiki/Physics" title="Physics">physics</a> and <a href="/wiki/Astronomy" title="Astronomy">astronomy</a> student who got into the habit of writing notes on his mathematical readings. In 1995 he put his notes online and called it "Eric's Treasure Trove of Mathematics." It contained hundreds of pages/articles, covering a wide range of mathematical topics. The site became popular as an extensive single resource on mathematics on the web. In 1998, he made a contract with <a href="/wiki/CRC_Press" title="CRC Press">CRC Press</a> and the contents of the site were published in print and <a href="/wiki/CD-ROM" title="CD-ROM">CD-ROM</a> form, titled "CRC Concise Encyclopedia of Mathematics." The free online version became only partially accessible to the public. In 1999 Weisstein went to work for Wolfram Research, Inc. (WRI), and WRI renamed the Math Treasure Trove to <i>MathWorld</i> and hosted it on the company's website<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2023)">citation needed</span></a></i>]</sup> without access restrictions.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2023)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="CRC_lawsuit">CRC lawsuit</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=2" title="Edit section: CRC lawsuit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In 2000, CRC Press sued <a href="/wiki/Wolfram_Research" title="Wolfram Research">Wolfram Research Inc. (WRI)</a>, WRI president <a href="/wiki/Stephen_Wolfram" title="Stephen Wolfram">Stephen Wolfram</a>, and author <a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Eric W. Weisstein</a>, due to what they considered a breach of contract: that the <i>MathWorld</i> content was to remain in print only. The site was taken down by a court <a href="/wiki/Injunction" title="Injunction">injunction</a>.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>The case was later settled out of court, with WRI paying an unspecified amount and complying with other <a href="/wiki/Stipulation" title="Stipulation">stipulations</a>. Among these stipulations is the inclusion of a copyright notice at the bottom of the website and broad rights for the CRC Press to produce <i>MathWorld</i> in printed book form. The site then became once again available free to the public.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2023)">citation needed</span></a></i>]</sup> </p><p>This case made a wave of headlines in online publishing circles. The <i><a href="/wiki/PlanetMath" title="PlanetMath">PlanetMath</a></i> project was a result of MathWorld's being unavailable.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=3" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/List_of_online_encyclopedias" title="List of online encyclopedias">List of online encyclopedias</a></li> <li><a href="/wiki/Wolfram_Mathematica" title="Wolfram Mathematica">Wolfram Mathematica</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=4" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.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-Making-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-Making_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-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.id-lock-limited a,.mw-parser-output .id-lock-registration.id-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.id-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}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.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:#085;margin-left:0.3em}.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}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFEric_Weisstein2007" class="citation journal cs1">Eric Weisstein (2007). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120709060020/http://www.mathematica-journal.com/issue/v10i3/MathWorld.html">"Making MathWorld"</a>. <i>Mathematica Journal</i>. <b>10</b> (3). Archived from <a rel="nofollow" class="external text" href="http://www.mathematica-journal.com/issue/v10i3/MathWorld.html">the original</a> on 2012-07-09<span class="reference-accessdate">. Retrieved <span class="nowrap">2010-08-22</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Mathematica+Journal&rft.atitle=Making+MathWorld&rft.volume=10&rft.issue=3&rft.date=2007&rft.au=Eric+Weisstein&rft_id=http%3A%2F%2Fwww.mathematica-journal.com%2Fissue%2Fv10i3%2FMathWorld.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMathWorld" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.worldcat.org/title/68697264">"Wolfram MathWorld : the web's most extensive mathematics resource | WorldCat.org"</a>. <i>www.worldcat.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-03-28</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.worldcat.org&rft.atitle=Wolfram+MathWorld+%3A+the+web%27s+most+extensive+mathematics+resource+%7C+WorldCat.org&rft_id=https%3A%2F%2Fwww.worldcat.org%2Ftitle%2F68697264&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMathWorld" class="Z3988"></span></span> </li> <li id="cite_note-:0-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-:0_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:0_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.mathematica-journal.com/2007/08/06/making-mathworld/">"Making MathWorld « The Mathematica Journal"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-03-28</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Making+MathWorld+%C2%AB+The+Mathematica+Journal&rft_id=https%3A%2F%2Fwww.mathematica-journal.com%2F2007%2F08%2F06%2Fmaking-mathworld%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMathWorld" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://casetext.com/case/crc-press-llc-v-wolfram-research-inc">"CRC Press, LLC v. Wolfram Research, Inc., 149 F. Supp. 2d 500 | Casetext Search + Citator"</a>. <i>casetext.com</i><span class="reference-accessdate">. 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