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arXiv · 2008.12217

Large monochromatic components in almost complete graphs and bipartite graphs

Zoltan Furedi·Ruth Luo
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Abstract

Gyárfas proved that every coloring of the edges of $K_n$ with $t+1$ colors contains a monochromatic connected component of size at least $n/t$. Later, Gyárfás and Sárközy asked for which values of $γ=γ(t)$ does the following strengthening for almost complete graphs hold: if $G$ is an $n$-vertex graph with minimum degree at least $(1-γ)n$, then every $(t+1)$-edge coloring of $G$ contains a monochromatic component of size at least $n/t$. We show $γ= 1/(6t^3)$ suffices, improving a result of DeBiasio, Krueger, and Sárközy.

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Zoltan Furedi, Ruth Luo. 2020-08-27. Large monochromatic components in almost complete graphs and bipartite graphs. https://arxiv.org/abs/2008.12217

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