Proof of a conjecture on induced subgraphs of Ramsey graphs
Proof of a conjecture on induced subgraphs of Ramsey graphs
复制标题
Ramsey 图的导出子图猜想的证明
DOI:
10.1090/tran/7729
复制
发表时间:
2017
影响因子:
1.3
通讯作者:
B. Sudakov
中科院分区:
文献类型:
--
作者:
Matthew Kwan;B. Sudakov
<p>An <inline-formula content-type="math/mathml">
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="n">
<mml:semantics>
<mml:mi>n</mml:mi>
<mml:annotation encoding="application/x-tex">n</mml:annotation>
</mml:semantics>
</mml:math>
</inline-formula>-vertex graph is called <italic><inline-formula content-type="math/mathml">
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper C">
<mml:semantics>
<mml:mi>C</mml:mi>
<mml:annotation encoding="application/x-tex">C</mml:annotation>
</mml:semantics>
</mml:math>
</inline-formula>-Ramsey</italic> if it has no clique or independent set of size <inline-formula content-type="math/mathml">
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper C log n">
<mml:semantics>
<mml:mrow>
<mml:mi>C</mml:mi>
<mml:mi>log</mml:mi>
<mml:mo><!-- --></mml:mo>
<mml:mi>n</mml:mi>
</mml:mrow>
<mml:annotation encoding="application/x-tex">C\log n</mml:annotation>
</mml:semantics>
</mml:math>
</inline-formula>. All known constructions of Ramsey graphs involve randomness in an essential way, and there is an ongoing line of research toward showing that in fact all Ramsey graphs must obey certain “richness” properties characteristic of random graphs. More than 25 years ago, Erdős, Faudree, and Sós conjectured that in any <inline-formula content-type="math/mathml">
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper C">
<mml:semantics>
<mml:mi>C</mml:mi>
<mml:annotation encoding="application/x-tex">C</mml:annotation>
</mml:semantics>
</mml:math>
</inline-formula>-Ramsey graph there are <inline-formula content-type="math/mathml">
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="normal upper Omega left-parenthesis n Superscript 5 slash 2 Baseline right-parenthesis">
<mml:semantics>
<mml:mrow>
<mml:mi mathvariant="normal">Ω<!-- Ω --></mml:mi>
<mml:mo stretchy="false">(</mml:mo>
<mml:msup>
<mml:mi>n</mml:mi>
<mml:mrow class="MJX-TeXAtom-ORD">
<mml:mn>5</mml:mn>
<mml:mrow class="MJX-TeXAtom-ORD">
<mml:mo>/</mml:mo>
</mml:mrow>
<mml:mn>2</mml:mn>
</mml:mrow>
</mml:msup>
<mml:mo stretchy="false">)</mml:mo>
</mml:mrow>
<mml:annotation encoding="application/x-tex">\Omega (n^{5/2})</mml:annotation>
</mml:semantics>
</mml:math>
</inline-formula> induced subgraphs, no pair of which have the same numbers of vertices and edges. Improving on earlier results of Alon, Balogh, Kostochka, and Samotij, in this paper we prove this conjecture.</p>
影响因子:
4.9
作者:
Chattopadhyay, Eshan;Zuckerman, David
通讯作者:
Zuckerman, David
影响因子:
--
作者:
Fox, Jacob;Sauermann, Lisa
通讯作者:
Sauermann, Lisa