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arXiv · 2601.15183

An update on multicolor Ramsey lower bounds

Marcelo Campos·Cosmin Pohoata
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Abstract

Building upon previous works by Conlon-Ferber and Wigderson, Sawin showed a few years ago that upper bounds on the minimum density of independent sets in a $K_t$-free $G$ can be used to provide lower bounds for multicolor Ramsey numbers. In this note, we observe how a further improved upper bound on this parameter directly follows from a recent spherical random geometric graph construction of Ma-Shen-Xie. As a consequence, we derive a small exponential improvement over the best known lower bounds for multicolor Ramsey numbers.

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Marcelo Campos, Cosmin Pohoata. 2026-01-21. An update on multicolor Ramsey lower bounds. https://arxiv.org/abs/2601.15183

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