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Upper and lower bounds - Wikipedia
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data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">This article is about precise bounds. For asymptotic bounds, see <a href="/wiki/Big_O_notation" title="Big O notation">Big O notation</a>.</div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Illustration_of_supremum.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/82/Illustration_of_supremum.svg/300px-Illustration_of_supremum.svg.png" decoding="async" width="300" height="96" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/82/Illustration_of_supremum.svg/450px-Illustration_of_supremum.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/82/Illustration_of_supremum.svg/600px-Illustration_of_supremum.svg.png 2x" data-file-width="282" data-file-height="90" /></a><figcaption>A set with upper bounds and its least upper bound</figcaption></figure> <p>In <a href="/wiki/Mathematics" title="Mathematics">mathematics</a>, particularly in <a href="/wiki/Order_theory" title="Order theory">order theory</a>, an <b>upper bound</b> or <b>majorant</b><sup id="cite_ref-schaefer_1-0" class="reference"><a href="#cite_note-schaefer-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> of a <a href="/wiki/Subset" title="Subset">subset</a> <span class="texhtml mvar" style="font-style:italic;">S</span> of some <a href="/wiki/Preorder" title="Preorder">preordered set</a> <span class="texhtml">(<i>K</i>, ≤)</span> is an element of <span class="texhtml mvar" style="font-style:italic;">K</span> that is <span class="nowrap"><a href="/wiki/Greater_than_or_equal_to" class="mw-redirect" title="Greater than or equal to">greater than or equal to</a></span> every element of <span class="texhtml mvar" style="font-style:italic;">S</span>.<sup id="cite_ref-MacLane-Birkhoff_2-0" class="reference"><a href="#cite_note-MacLane-Birkhoff-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><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> <a href="/wiki/Duality_(order_theory)" title="Duality (order theory)">Dually</a>, a <b>lower bound</b> or <b>minorant</b> of <span class="texhtml mvar" style="font-style:italic;">S</span> is defined to be an element of <span class="texhtml mvar" style="font-style:italic;">K</span> that is less than or equal to every element of <span class="texhtml mvar" style="font-style:italic;">S</span>. A set with an upper (respectively, lower) bound is said to be <b>bounded from above</b> or <b>majorized</b><sup id="cite_ref-schaefer_1-1" class="reference"><a href="#cite_note-schaefer-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> (respectively <b>bounded from below</b> or <b>minorized</b>) by that bound. The terms <b>bounded above</b> (<b>bounded below</b>) are also used in the mathematical literature for sets that have upper (respectively lower) bounds.<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> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Examples">Examples</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Upper_and_lower_bounds&action=edit&section=1" title="Edit section: Examples"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>For example, <span class="texhtml">5</span> is a lower bound for the set <span class="texhtml"><i>S</i> = {5, 8, 42, 34, 13934}</span> (as a subset of the <a href="/wiki/Integers" class="mw-redirect" title="Integers">integers</a> or of the <a href="/wiki/Real_numbers" class="mw-redirect" title="Real numbers">real numbers</a>, etc.), and so is <span class="texhtml">4</span>. On the other hand, <span class="texhtml">6</span> is not a lower bound for <span class="texhtml mvar" style="font-style:italic;">S</span> since it is not smaller than every element in <span class="texhtml mvar" style="font-style:italic;">S</span>. <span class="texhtml">13934</span> and other numbers <i>x</i> such that <span class="texhtml">x ≥ 13934</span> would be an upper bound for <i>S</i>. </p><p>The set <span class="texhtml"><i>S</i> = {42}</span> has <span class="texhtml">42</span> as both an upper bound and a lower bound; all other numbers are either an upper bound or a lower bound for that <span class="texhtml mvar" style="font-style:italic;">S</span>. </p><p>Every subset of the <a href="/wiki/Natural_number" title="Natural number">natural numbers</a> has a lower bound since the natural numbers have a least element (0 or 1, depending on convention). An infinite subset of the natural numbers cannot be bounded from above. An infinite subset of the integers may be bounded from below or bounded from above, but not both. An infinite subset of the <a href="/wiki/Rational_number" title="Rational number">rational numbers</a> may or may not be bounded from below, and may or may not be bounded from above. </p><p>Every finite subset of a non-empty <a href="/wiki/Totally_ordered_set" class="mw-redirect" title="Totally ordered set">totally ordered set</a> has both upper and lower bounds. </p> <div class="mw-heading mw-heading2"><h2 id="Bounds_of_functions">Bounds of functions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Upper_and_lower_bounds&action=edit&section=2" title="Edit section: Bounds of functions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The definitions can be generalized to <a href="/wiki/Function_(mathematics)" title="Function (mathematics)">functions</a> and even to sets of functions. </p><p>Given a function <span style="padding-right:0.15em;"><span class="texhtml mvar" style="font-style:italic;">f</span></span> with <a href="/wiki/Domain_of_a_function" title="Domain of a function">domain</a> <span class="texhtml mvar" style="font-style:italic;">D</span> and a preordered set <span class="texhtml">(<i>K</i>, ≤)</span> as <a href="/wiki/Codomain" title="Codomain">codomain</a>, an element <span class="texhtml mvar" style="font-style:italic;"><i>y</i></span> of <span class="texhtml mvar" style="font-style:italic;">K</span> is an upper bound of <span style="padding-right:0.15em;"><span class="texhtml mvar" style="font-style:italic;">f</span></span> if <span class="texhtml"><i>y</i> ≥ <span style="padding-right:0.15em;"><i>f</i></span>(<i>x</i>)</span> for each <span class="texhtml mvar" style="font-style:italic;">x</span> in <span class="texhtml mvar" style="font-style:italic;">D</span>. The upper bound is called <i><a href="/wiki/Mathematical_jargon#sharp" class="mw-redirect" title="Mathematical jargon">sharp</a></i> if equality holds for at least one value of <span class="texhtml mvar" style="font-style:italic;">x</span>. It indicates that the constraint is optimal, and thus cannot be further reduced without invalidating the inequality. </p><p>Similarly, a function <span class="texhtml mvar" style="font-style:italic;">g</span> defined on domain <span class="texhtml mvar" style="font-style:italic;">D</span> and having the same codomain <span class="texhtml">(<i>K</i>, ≤)</span> is an upper bound of <span style="padding-right:0.15em;"><span class="texhtml mvar" style="font-style:italic;">f</span></span>, if <span class="texhtml"><i>g</i>(<i>x</i>) ≥ <span style="padding-right:0.15em;"><i>f</i></span>(<i>x</i>)</span> for each <span class="texhtml mvar" style="font-style:italic;">x</span> in <span class="texhtml mvar" style="font-style:italic;">D</span>. The function <span class="texhtml mvar" style="font-style:italic;">g</span> is further said to be an upper bound of a set of functions, if it is an upper bound of <i>each</i> function in that set. </p><p>The notion of lower bound for (sets of) functions is defined analogously, by replacing ≥ with ≤. </p> <div class="mw-heading mw-heading2"><h2 id="Tight_bounds">Tight bounds</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Upper_and_lower_bounds&action=edit&section=3" title="Edit section: Tight bounds"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An upper bound is said to be a <i>tight upper bound</i>, a <i>least upper bound</i>, or a <i><a href="/wiki/Supremum" class="mw-redirect" title="Supremum">supremum</a></i>, if no smaller value is an upper bound. Similarly, a lower bound is said to be a <i>tight lower bound</i>, a <i>greatest lower bound</i>, or an <i><a href="/wiki/Infimum" class="mw-redirect" title="Infimum">infimum</a></i>, if no greater value is a lower bound. </p> <div class="mw-heading mw-heading2"><h2 id="Exact_upper_bounds">Exact upper bounds</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Upper_and_lower_bounds&action=edit&section=4" title="Edit section: Exact upper bounds"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An upper bound <span class="texhtml mvar" style="font-style:italic;">u</span> of a subset <span class="texhtml mvar" style="font-style:italic;">S</span> of a preordered set <span class="texhtml">(<i>K</i>, ≤)</span> is said to be an <i>exact upper bound</i> for <span class="texhtml mvar" style="font-style:italic;">S</span> if every element of <span class="texhtml mvar" style="font-style:italic;">K</span> that is strictly majorized by <span class="texhtml mvar" style="font-style:italic;">u</span> is also majorized by some element of <span class="texhtml mvar" style="font-style:italic;">S</span>. Exact upper bounds of <a href="/wiki/Reduced_product" title="Reduced product">reduced products</a> of <a href="/wiki/Linear_order" class="mw-redirect" title="Linear order">linear orders</a> play an important role in <a href="/wiki/PCF_theory" title="PCF theory">PCF theory</a>.<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=Upper_and_lower_bounds&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Greatest_element_and_least_element" title="Greatest element and least element">Greatest element and least element</a></li> <li><a href="/wiki/Infimum_and_supremum" title="Infimum and supremum">Infimum and supremum</a></li> <li><a href="/wiki/Maximal_and_minimal_elements" title="Maximal and minimal elements">Maximal and minimal elements</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=Upper_and_lower_bounds&action=edit&section=6" 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-schaefer-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-schaefer_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-schaefer_1-1"><sup><i><b>b</b></i></sup></a></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="CITEREFSchaeferWolff1999" class="citation book cs1"><a href="/wiki/Helmut_H._Schaefer" title="Helmut H. Schaefer">Schaefer, Helmut H.</a>; Wolff, Manfred P. (1999). <i>Topological Vector Spaces</i>. <a href="/wiki/Graduate_Texts_in_Mathematics" title="Graduate Texts in Mathematics">GTM</a>. Vol. 8. New York, NY: Springer New York Imprint Springer. p. 3. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-4612-7155-0" title="Special:BookSources/978-1-4612-7155-0"><bdi>978-1-4612-7155-0</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/840278135">840278135</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Topological+Vector+Spaces&rft.place=New+York%2C+NY&rft.series=GTM&rft.pages=3&rft.pub=Springer+New+York+Imprint+Springer&rft.date=1999&rft_id=info%3Aoclcnum%2F840278135&rft.isbn=978-1-4612-7155-0&rft.aulast=Schaefer&rft.aufirst=Helmut+H.&rft.au=Wolff%2C+Manfred+P.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AUpper+and+lower+bounds" class="Z3988"></span> </span> </li> <li id="cite_note-MacLane-Birkhoff-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-MacLane-Birkhoff_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMac_LaneBirkhoff1991" class="citation book cs1"><a href="/wiki/Saunders_Mac_Lane" title="Saunders Mac Lane">Mac Lane, Saunders</a>; <a href="/wiki/Garrett_Birkhoff" title="Garrett Birkhoff">Birkhoff, Garrett</a> (1991). <span class="id-lock-limited" title="Free access subject to limited trial, subscription normally required"><a rel="nofollow" class="external text" href="https://archive.org/details/algebra00lane"><i>Algebra</i></a></span>. Providence, RI: <a href="/wiki/American_Mathematical_Society" title="American Mathematical Society">American Mathematical Society</a>. p. <a rel="nofollow" class="external text" href="https://archive.org/details/algebra00lane/page/n164">145</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-8218-1646-2" title="Special:BookSources/0-8218-1646-2"><bdi>0-8218-1646-2</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Algebra&rft.place=Providence%2C+RI&rft.pages=145&rft.pub=American+Mathematical+Society&rft.date=1991&rft.isbn=0-8218-1646-2&rft.aulast=Mac+Lane&rft.aufirst=Saunders&rft.au=Birkhoff%2C+Garrett&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Falgebra00lane&rfr_id=info%3Asid%2Fen.wikipedia.org%3AUpper+and+lower+bounds" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</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.mathsisfun.com/definitions/upper-bound.html">"Upper Bound Definition (Illustrated Mathematics Dictionary)"</a>. <i>Math is Fun</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2019-12-03</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Math+is+Fun&rft.atitle=Upper+Bound+Definition+%28Illustrated+Mathematics+Dictionary%29&rft_id=https%3A%2F%2Fwww.mathsisfun.com%2Fdefinitions%2Fupper-bound.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AUpper+and+lower+bounds" 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 id="CITEREFWeisstein" class="citation web cs1">Weisstein, Eric W. <a rel="nofollow" class="external text" href="http://mathworld.wolfram.com/UpperBound.html">"Upper Bound"</a>. <i>mathworld.wolfram.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2019-12-03</span></span>.</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=Upper+Bound&rft.aulast=Weisstein&rft.aufirst=Eric+W.&rft_id=http%3A%2F%2Fmathworld.wolfram.com%2FUpperBound.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AUpper+and+lower+bounds" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKojman1998" class="citation journal cs1">Kojman, Menachem (21 August 1998). <a rel="nofollow" class="external text" href="https://www.sciencedirect.com/science/article/pii/S0168007298000116">"Exact upper bounds and their uses in set theory"</a>. <i>Annals of Pure and Applied Logic</i>. <b>92</b> (3): 267–282. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0168-0072%2898%2900011-6">10.1016/S0168-0072(98)00011-6</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Annals+of+Pure+and+Applied+Logic&rft.atitle=Exact+upper+bounds+and+their+uses+in+set+theory&rft.volume=92&rft.issue=3&rft.pages=267-282&rft.date=1998-08-21&rft_id=info%3Adoi%2F10.1016%2FS0168-0072%2898%2900011-6&rft.aulast=Kojman&rft.aufirst=Menachem&rft_id=https%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS0168007298000116&rfr_id=info%3Asid%2Fen.wikipedia.org%3AUpper+and+lower+bounds" class="Z3988"></span></span> </li> </ol></div></div> <!-- NewPP limit report Parsed by mw‐web.eqiad.main‐5dc468848‐64mx2 Cached time: 20241122140345 Cache expiry: 2592000 Reduced expiry: false Complications: [vary‐revision‐sha1, show‐toc] CPU time usage: 0.194 seconds Real time usage: 0.267 seconds Preprocessor visited node count: 1411/1000000 Post‐expand include size: 15146/2097152 bytes Template argument size: 1970/2097152 bytes Highest expansion depth: 8/100 Expensive parser function count: 2/500 Unstrip recursion depth: 1/20 Unstrip post‐expand size: 19078/5000000 bytes Lua time usage: 0.108/10.000 seconds Lua memory usage: 4494528/52428800 bytes Number of Wikibase entities loaded: 0/400 --> <!-- Transclusion expansion time report (%,ms,calls,template) 100.00% 239.653 1 -total 47.94% 114.892 1 Template:Reflist 34.90% 83.637 2 Template:Cite_book 28.79% 68.988 1 Template:Short_description 16.17% 38.741 2 Template:Pagetype 9.22% 22.090 1 Template:About 8.37% 20.064 17 Template:Main_other 8.16% 19.559 14 Template:Math 6.68% 16.006 1 Template:SDcat 3.10% 7.433 2 Template:Cite_web --> <!-- Saved in parser cache with key enwiki:pcache:42693:|#|:idhash:canonical and timestamp 20241122140345 and revision id 1247871023. 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