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An improved lower bound for multicolor Ramsey numbers and the half-multiplicity Ramsey number problem

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 نشر من قبل Will Sawin
 تاريخ النشر 2021
  مجال البحث
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 تأليف Will Sawin




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The multicolor Ramsey number problem asks, for each pair of natural numbers $ell$ and $t$, for the largest $ell$-coloring of a complete graph with no monochromatic clique of size $t$. Recent works of Conlon-Ferber and Wigderson have improved the longstanding lower bound for this problem. We make a further improvement by replacing an explicit graph appearing in their constructions by a random graph. Graphs useful for this construction are exactly those relevant for a problem of ErdH{o}s on graphs with no large cliques and few large independent sets. We also make some basic observations about this problem.



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