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arXiv · 2312.13965

The growth rate of multicolor Ramsey numbers of $3$-graphs

Domagoj Bradač·Jacob Fox·Benny Sudakov
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Abstract

The $q$-color Ramsey number of a $k$-uniform hypergraph $G,$ denoted $r(G;q)$, is the minimum integer $N$ such that any coloring of the edges of the complete $k$-uniform hypergraph on $N$ vertices contains a monochromatic copy of $G$. The study of these numbers is one of the most central topics in combinatorics. One natural question, which for triangles goes back to the work of Schur in 1916, is to determine the behaviour of $r(G;q)$ for fixed $G$ and $q$ tending to infinity. In this paper we study this problem for $3$-uniform hypergraphs and determine the tower height of $r(G;q)$ as a function of $q$. More precisely, given a hypergraph $G$, we determine when $r(G; q)$ behaves polynomially, exponentially or double-exponentially in $q$. This answers a question of Axenovich, Gyárfás, Liu and Mubayi.

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Domagoj Bradač, Jacob Fox, Benny Sudakov. 2024-04-29. The growth rate of multicolor Ramsey numbers of $3$-graphs. https://arxiv.org/abs/2312.13965

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