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<h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Conjecture de Singmaster</span></h1>
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<div id="mw-content-text" class="mw-body-content mw-content-ltr" lang="fr" dir="ltr"><div class="mw-content-ltr mw-parser-output" lang="fr" dir="ltr"><p>La <b>conjecture de Singmaster</b>, nommée ainsi en l'honneur de <a href="David_Singmaster" title="David Singmaster">David Singmaster</a>, affirme qu'il y a un <a href="Majorant" class="mw-redirect" title="Majorant">majorant</a> fini des multiplicités des termes du <a href="Triangle_de_Pascal" title="Triangle de Pascal">triangle de Pascal</a> (autres que 1 qui apparaît un nombre infini de fois), à savoir le nombre de fois où un terme apparaît dans le triangle. <a href="Paul_Erd%C5%91s" title="Paul Erdős">Paul Erdős</a> a dit que la conjecture de Singmaster était probablement vraie mais qu'elle serait très difficile à démontrer.
</p>
<div class="mw-heading mw-heading2"><h2 id="Conjecture_et_résultats_connus"><span id="Conjecture_et_r.C3.A9sultats_connus"></span>Conjecture et résultats connus</h2></div>
<p>Il est clair que le seul nombre qui apparaît une infinité de fois dans le triangle de Pascal est 1 car tout autre nombre <i>x</i> ne peut apparaître que dans les <i>x</i> + 1 premières lignes du triangle.
</p><p>Soit <i>N</i>(<i>a</i>) le nombre de fois où le nombre <i>a</i> > 1 apparaît dans le triangle de Pascal. En notation « <a href="Comparaison_asymptotique" title="Comparaison asymptotique">grand O de</a> », la conjecture affirme que :
</p>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle N(a)=O(1).}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>N</mi>
<mo stretchy="false">(</mo>
<mi>a</mi>
<mo stretchy="false">)</mo>
<mo>=</mo>
<mi>O</mi>
<mo stretchy="false">(</mo>
<mn>1</mn>
<mo stretchy="false">)</mo>
<mo>.</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle N(a)=O(1).}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/d921fc61e7b922cdb6f2b399cee44f3d525184d8.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:13.593ex; height:2.843ex;" alt="{\displaystyle N(a)=O(1).}" loading="lazy"></span></dd></dl>
<p>Singmaster a montré<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> que
</p>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle N(a)=O(\log a).}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>N</mi>
<mo stretchy="false">(</mo>
<mi>a</mi>
<mo stretchy="false">)</mo>
<mo>=</mo>
<mi>O</mi>
<mo stretchy="false">(</mo>
<mi>log</mi>
<mo><!-- --></mo>
<mi>a</mi>
<mo stretchy="false">)</mo>
<mo>.</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle N(a)=O(\log a).}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/6fdcce4c38f609f70b67e43077ad43645babcb30.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:17.019ex; height:2.843ex;" alt="{\displaystyle N(a)=O(\log a).}" loading="lazy"></span></dd></dl>
<p>Abbot, <a href="Paul_Erd%C5%91s" title="Paul Erdős">Erdős</a>, et Hanson<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> affinèrent l'estimation. La meilleure limite actuelle, due à <a href="Daniel_Kane_(math%C3%A9maticien)" title="Daniel Kane (mathématicien)">Daniel Kane</a><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>, est
</p>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle N(a)=O\left({\frac {(\log a)(\log \log \log a)}{(\log \log a)^{3}}}\right).}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>N</mi>
<mo stretchy="false">(</mo>
<mi>a</mi>
<mo stretchy="false">)</mo>
<mo>=</mo>
<mi>O</mi>
<mrow>
<mo>(</mo>
<mrow class="MJX-TeXAtom-ORD">
<mfrac>
<mrow>
<mo stretchy="false">(</mo>
<mi>log</mi>
<mo><!-- --></mo>
<mi>a</mi>
<mo stretchy="false">)</mo>
<mo stretchy="false">(</mo>
<mi>log</mi>
<mo><!-- --></mo>
<mi>log</mi>
<mo><!-- --></mo>
<mi>log</mi>
<mo><!-- --></mo>
<mi>a</mi>
<mo stretchy="false">)</mo>
</mrow>
<mrow>
<mo stretchy="false">(</mo>
<mi>log</mi>
<mo><!-- --></mo>
<mi>log</mi>
<mo><!-- --></mo>
<mi>a</mi>
<msup>
<mo stretchy="false">)</mo>
<mrow class="MJX-TeXAtom-ORD">
<mn>3</mn>
</mrow>
</msup>
</mrow>
</mfrac>
</mrow>
<mo>)</mo>
</mrow>
<mo>.</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle N(a)=O\left({\frac {(\log a)(\log \log \log a)}{(\log \log a)^{3}}}\right).}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/0e78041098e8a91a59354eb0e882c25a704a9bb4.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:35.166ex; height:6.509ex;" alt="{\displaystyle N(a)=O\left({\frac {(\log a)(\log \log \log a)}{(\log \log a)^{3}}}\right).}" loading="lazy"></span></dd></dl>
<p>Singmaster a montré<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> que l'<a href="%C3%89quation_diophantienne" title="Équation diophantienne">équation diophantienne</a>
</p>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {m \choose j-1}={m-1 \choose j}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mi>m</mi>
<mrow>
<mi>j</mi>
<mo>−<!-- − --></mo>
<mn>1</mn>
</mrow>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
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<mfrac linethickness="0">
<mrow>
<mi>m</mi>
<mo>−<!-- − --></mo>
<mn>1</mn>
</mrow>
<mi>j</mi>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {m \choose j-1}={m-1 \choose j}}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/bedc0f4d1d8316485254a2f318d9a2279df74ff6.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:20.945ex; height:6.176ex;" alt="{\displaystyle {m \choose j-1}={m-1 \choose j}}" loading="lazy"></span></dd></dl>
<p>a une infinité de solutions (<i>m</i>, <i>j</i>). Il s'ensuit qu'il y a une infinité de termes de multiplicité au moins 6. Les solutions sont données par<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>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle m=F_{2\ell }F_{2\ell +1}\quad {\rm {et}}\quad j=F_{2\ell -1}F_{2\ell },}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>m</mi>
<mo>=</mo>
<msub>
<mi>F</mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
<mi>ℓ<!-- ℓ --></mi>
</mrow>
</msub>
<msub>
<mi>F</mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
<mi>ℓ<!-- ℓ --></mi>
<mo>+</mo>
<mn>1</mn>
</mrow>
</msub>
<mspace width="1em"></mspace>
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="normal">e</mi>
<mi mathvariant="normal">t</mi>
</mrow>
</mrow>
<mspace width="1em"></mspace>
<mi>j</mi>
<mo>=</mo>
<msub>
<mi>F</mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
<mi>ℓ<!-- ℓ --></mi>
<mo>−<!-- − --></mo>
<mn>1</mn>
</mrow>
</msub>
<msub>
<mi>F</mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
<mi>ℓ<!-- ℓ --></mi>
</mrow>
</msub>
<mo>,</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle m=F_{2\ell }F_{2\ell +1}\quad {\rm {et}}\quad j=F_{2\ell -1}F_{2\ell },}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/60da1a0930582c16ce1675c80f89713a2f014948.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:33.563ex; height:2.509ex;" alt="{\displaystyle m=F_{2\ell }F_{2\ell +1}\quad {\rm {et}}\quad j=F_{2\ell -1}F_{2\ell },}" loading="lazy"></span></dd></dl>
<p>où <i>ℓ</i> ≥ 2 et <i>F<sub>n</sub></i> est le <i>n</i>-ième <a href="Nombre_de_Fibonacci" class="mw-redirect" title="Nombre de Fibonacci">nombre de Fibonacci</a> (indicé selon la convention suivante : <i>F</i><sub>1</sub> = <i>F</i><sub>2</sub> = 1).
</p>
<div class="mw-heading mw-heading2"><h2 id="Exemples_numériques"><span id="Exemples_num.C3.A9riques"></span>Exemples numériques</h2></div>
<ul><li>2 apparaît une seule fois ; tout nombre plus grand apparaît plus d'une fois.</li>
<li>4, ainsi que tout <a href="Nombre_premier" title="Nombre premier">nombre premier</a> différent de 2, apparaît 2 fois.</li>
<li>6 apparaît 3 fois.</li>
<li>Beaucoup de nombres apparaissent 4 fois.</li>
<li>On ne sait pas s'il existe des nombres apparaissant 5 fois.</li>
<li>Les sept nombres suivants apparaissent 6 fois :</li></ul>
<dl><dd><dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {120 \choose 1}={16 \choose 2}={10 \choose 3},}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>120</mn>
<mn>1</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>16</mn>
<mn>2</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>10</mn>
<mn>3</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>,</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {120 \choose 1}={16 \choose 2}={10 \choose 3},}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/d893c6cfdb084018714dde50c4f3f7f09ed8d26d.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:25.244ex; height:6.176ex;" alt="{\displaystyle {120 \choose 1}={16 \choose 2}={10 \choose 3},}" loading="lazy"></span></dd></dl></dd></dl>
<p><br>
</p>
<dl><dd><dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {210 \choose 1}={21 \choose 2}={10 \choose 4},}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>210</mn>
<mn>1</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>21</mn>
<mn>2</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>10</mn>
<mn>4</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>,</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {210 \choose 1}={21 \choose 2}={10 \choose 4},}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/6733126545a8538bdd5a654e0fb6429e2bffe4dd.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:25.244ex; height:6.176ex;" alt="{\displaystyle {210 \choose 1}={21 \choose 2}={10 \choose 4},}" loading="lazy"></span></dd></dl></dd></dl>
<p><br>
</p>
<dl><dd><dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {1540 \choose 1}={56 \choose 2}={22 \choose 3},}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>1540</mn>
<mn>1</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>56</mn>
<mn>2</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
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<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>22</mn>
<mn>3</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>,</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {1540 \choose 1}={56 \choose 2}={22 \choose 3},}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/2a890b2294feef689c0c4b7f4444006fac076bae.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:26.407ex; height:6.176ex;" alt="{\displaystyle {1540 \choose 1}={56 \choose 2}={22 \choose 3},}" loading="lazy"></span></dd></dl></dd></dl>
<p><br>
</p>
<dl><dd><dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {7140 \choose 1}={120 \choose 2}={36 \choose 3},}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
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<annotation encoding="application/x-tex">{\displaystyle {7140 \choose 1}={120 \choose 2}={36 \choose 3},}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/a07660816870b465dd2b79f1f82f292ce8d9f713.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:27.569ex; height:6.176ex;" alt="{\displaystyle {7140 \choose 1}={120 \choose 2}={36 \choose 3},}" loading="lazy"></span></dd></dl></dd></dl>
<p><br>
</p>
<dl><dd><dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {11628 \choose 1}={153 \choose 2}={19 \choose 5},}">
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<annotation encoding="application/x-tex">{\displaystyle {11628 \choose 1}={153 \choose 2}={19 \choose 5},}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/a1b3015a2c53391ff807f3959f0002359dcc680a.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:28.732ex; height:6.176ex;" alt="{\displaystyle {11628 \choose 1}={153 \choose 2}={19 \choose 5},}" loading="lazy"></span></dd></dl></dd></dl>
<p><br>
</p>
<dl><dd><dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {24310 \choose 1}={221 \choose 2}={17 \choose 8},}">
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<annotation encoding="application/x-tex">{\displaystyle {24310 \choose 1}={221 \choose 2}={17 \choose 8},}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/0c5c7fc4f18eafc6f689ab81edef0a2e5614f100.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:28.732ex; height:6.176ex;" alt="{\displaystyle {24310 \choose 1}={221 \choose 2}={17 \choose 8},}" loading="lazy"></span></dd></dl></dd></dl>
<dl><dd><dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {61218182743304701891431482520 \choose 1}={104 \choose 39}={103 \choose 40},}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
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<mrow class="MJX-TeXAtom-ORD">
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<mn>61218182743304701891431482520</mn>
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<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
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<mn>103</mn>
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<annotation encoding="application/x-tex">{\displaystyle {61218182743304701891431482520 \choose 1}={104 \choose 39}={103 \choose 40},}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/2966f7a7e2d1daa22ccc1c30f9b5278227f21479.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:57.793ex; height:6.176ex;" alt="{\displaystyle {61218182743304701891431482520 \choose 1}={104 \choose 39}={103 \choose 40},}" loading="lazy"></span>
<dl><dd>qui correspond à <i>ℓ</i> = 3 dans la suite de Singmaster.</dd></dl></dd></dl></dd></dl>
<ul><li>Parmi les autres nombres apparaissant au moins 7 fois, le plus petit est le précédent dans la suite de Singmaster (<i>ℓ</i> = 2). Il apparaît 8 fois :<span style="display: block; margin-left:1.6em;"><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {3003 \choose 1}={78 \choose 2}={15 \choose 5}={14 \choose 6}.}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>3003</mn>
<mn>1</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
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<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
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<mfrac linethickness="0">
<mn>78</mn>
<mn>2</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
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<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>15</mn>
<mn>5</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mrow class="MJX-TeXAtom-OPEN">
<mo maxsize="2.047em" minsize="2.047em">(</mo>
</mrow>
<mfrac linethickness="0">
<mn>14</mn>
<mn>6</mn>
</mfrac>
<mrow class="MJX-TeXAtom-CLOSE">
<mo maxsize="2.047em" minsize="2.047em">)</mo>
</mrow>
</mrow>
</mrow>
<mo>.</mo>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {3003 \choose 1}={78 \choose 2}={15 \choose 5}={14 \choose 6}.}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/191e54215cd2a7747b56a5f961483509d51d31b5.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:35.251ex; height:6.176ex;" alt="{\displaystyle {3003 \choose 1}={78 \choose 2}={15 \choose 5}={14 \choose 6}.}" loading="lazy"></span></span>On ne sait pas s'il existe d'autres nombres apparaissant au moins 7 fois.</li></ul>
<div class="mw-heading mw-heading2"><h2 id="Voir_aussi">Voir aussi</h2></div>
<div class="mw-heading mw-heading3"><h3 id="Notes_et_références"><span id="Notes_et_r.C3.A9f.C3.A9rences"></span>Notes et références</h3></div>
<div style="font-size:85%; padding-left:1.6em; margin:0.3em 0;"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> Cet article est partiellement ou en totalité issu de l’article de Wikipédia en anglais intitulé <span class="">« <a class="external text" href="https://en.wikipedia.org/wiki/Singmaster%27s_conjecture?oldid=435034951">Singmaster's conjecture</a> » <small>(<a class="external text" href="https://en.wikipedia.org/wiki/Singmaster%27s_conjecture?action=history">voir la liste des auteurs</a>)</small></span>.</div>
<div class="references-small decimal" style=""><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"><span class="ouvrage" id="D._Singmaster1971"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> <span class="nom_auteur">D. Singmaster</span>, « <cite style="font-style:normal" lang="en">Research Problems: How often does an integer occur as a binomial coefficient?</cite> », <i><span class="lang-en" lang="en"><a href="American_Mathematical_Monthly" class="mw-redirect" title="American Mathematical Monthly">Amer. Math. Monthly</a></span></i>, <abbr class="abbr" title="volume">vol.</abbr> 78, <abbr class="abbr" title="numéro">n<sup>o</sup></abbr> 4, <time>1971</time>, <abbr class="abbr" title="pages">p.</abbr> <span class="nowrap">385–386</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Research+Problems%3A+How+often+does+an+integer+occur+as+a+binomial+coefficient%3F&rft.jtitle=Amer.+Math.+Monthly&rft.issue=4&rft.aulast=D.+Singmaster&rft.date=1971&rft.volume=78&rft.pages=385%E2%80%93386&rfr_id=info%3Asid%2Ffr.wikipedia.org%3AConjecture+de+Singmaster"></span></span>.</span>
</li>
<li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">↑</a> </span><span class="reference-text"><span class="ouvrage" id="H._L._Abbott,_Paul_Erdős_et_D._Hanson1974"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> <span class="nom_auteur">H. L. Abbott, Paul Erdős et D. Hanson</span>, « <cite style="font-style:normal" lang="en">On the number of times an integer occurs as a binomial coefficient</cite> », <i><span class="lang-en" lang="en">Amer. Math. Monthly</span></i>, <abbr class="abbr" title="volume">vol.</abbr> 81, <abbr class="abbr" title="numéro">n<sup>o</sup></abbr> 3, <time>1974</time>, <abbr class="abbr" title="pages">p.</abbr> <span class="nowrap">256–261</span> <small style="line-height:1em;">(<a href="Digital_Object_Identifier" title="Digital Object Identifier">DOI</a> <span class=" noarchive nowrap"><a rel="nofollow" class="external text" href="https://dx.doi.org/10.2307/2319526">10.2307/2319526</a></span>)</small><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=On+the+number+of+times+an+integer+occurs+as+a+binomial+coefficient&rft.jtitle=Amer.+Math.+Monthly&rft.issue=3&rft.aulast=H.+L.+Abbott%2C+Paul+Erd%C5%91s+et+D.+Hanson&rft.date=1974&rft.volume=81&rft.pages=256%E2%80%93261&rft_id=info%3Adoi%2F10.2307%2F2319526&rfr_id=info%3Asid%2Ffr.wikipedia.org%3AConjecture+de+Singmaster"></span></span>.</span>
</li>
<li id="cite_note-3"><span class="mw-cite-backlink"><a href="#cite_ref-3">↑</a> </span><span class="reference-text"><span class="ouvrage" id="Daniel_M._Kane2007"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> <span class="nom_auteur">Daniel M. Kane</span>, « <cite style="font-style:normal" lang="en">Improved bounds on the number of ways of expressing <i>t</i> as a binomial coefficient</cite> », <i><span class="lang-en" lang="en">Integers: Electronic Journal of Combinatorial Number Theory</span></i>, <abbr class="abbr" title="volume">vol.</abbr> 7, <time>2007</time>, #A53 <small style="line-height:1em;">(<a rel="nofollow" class="external text" href="http://www.emis.de/journals/INTEGERS/papers/h53/h53.pdf">lire en ligne</a>)</small><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Improved+bounds+on+the+number+of+ways+of+expressing+%27%27t%27%27++as+a+binomial+coefficient&rft.jtitle=Integers%3A+Electronic+Journal+of+Combinatorial+Number+Theory&rft.aulast=Daniel+M.+Kane&rft.date=2007&rft.volume=7&rft.pages=%23A53&rft_id=http%3A%2F%2Fwww.emis.de%2Fjournals%2FINTEGERS%2Fpapers%2Fh53%2Fh53.pdf&rfr_id=info%3Asid%2Ffr.wikipedia.org%3AConjecture+de+Singmaster"></span></span>.</span>
</li>
<li id="cite_note-4"><span class="mw-cite-backlink"><a href="#cite_ref-4">↑</a> </span><span class="reference-text"><span class="ouvrage" id="D._Singmaster1975"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> <span class="nom_auteur">D. Singmaster</span>, « <cite style="font-style:normal" lang="en">Repeated binomial coefficients and Fibonacci numbers</cite> », <i><span class="lang-en" lang="en"><a href="Fibonacci_Quarterly" title="Fibonacci Quarterly">Fibonacci Quarterly</a></span></i>, <abbr class="abbr" title="volume">vol.</abbr> 13, <abbr class="abbr" title="numéro">n<sup>o</sup></abbr> 4, <time>1975</time>, <abbr class="abbr" title="pages">p.</abbr> <span class="nowrap">295-298</span> <small style="line-height:1em;">(<a rel="nofollow" class="external text" href="http://www.fq.math.ca/Scanned/13-4/singmaster.pdf">lire en ligne</a>)</small><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Repeated+binomial+coefficients+and+Fibonacci+numbers&rft.jtitle=Fibonacci+Quarterly&rft.issue=4&rft.aulast=D.+Singmaster&rft.date=1975&rft.volume=13&rft.pages=295-298&rft_id=http%3A%2F%2Fwww.fq.math.ca%2FScanned%2F13-4%2Fsingmaster.pdf&rfr_id=info%3Asid%2Ffr.wikipedia.org%3AConjecture+de+Singmaster"></span></span>.</span>
</li>
<li id="cite_note-5"><span class="mw-cite-backlink"><a href="#cite_ref-5">↑</a> </span><span class="reference-text">Voir <span class="ouvrage" id="Weisstein"><span class="ouvrage" id="Eric_W._Weisstein"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> <a href="Eric_W._Weisstein" title="Eric W. Weisstein">Eric W. Weisstein</a>, « <a rel="nofollow" class="external text" href="http://mathworld.wolfram.com/PascalsTriangle.html"><cite style="font-style:normal;" lang="en"><span class="lang-en" lang="en">Pascal's Triangle</span></cite></a> », sur <span class="italique"><a href="MathWorld" title="MathWorld">MathWorld</a></span></span></span> et suite <a href="https://oeis.org/A003015" class="extiw external" title="oeis:A003015">A003015</a> de l'<a href="Encyclop%C3%A9die_en_ligne_des_suites_de_nombres_entiers" title="Encyclopédie en ligne des suites de nombres entiers">OEIS</a>.</span>
</li>
</ol></div>
</div>
<div class="mw-heading mw-heading3"><h3 id="Liens_externes">Liens externes</h3></div>
<ul><li>Bruno Martin — « Une conjecture sur le triangle de Pascal » — <a href="Images_des_Math%C3%A9matiques" class="mw-redirect" title="Images des Mathématiques">Images des Mathématiques</a>, CNRS, 2021</li></ul>
<ul id="bandeau-portail" class="bandeau-portail"><li><span class="bandeau-portail-element"><span class="bandeau-portail-icone"><span class="noviewer skin-invert-image" typeof="mw:File"></span></span> <span class="bandeau-portail-texte">Arithmétique et théorie des nombres</span> </span></li> </ul></div><!--htdig_noindex--><div><div class="zim-footer">
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