English

The hat guessing number of random graphs with constant edge-chosen probability

Combinatorics 2023-02-09 v1

Abstract

Let GG be a graph with nn vertices. The {\em hat guessing number} of GG is defined in terms of the following game: There are nn players and one opponent. The opponent will wear one of the qq hats of different colors on the player's head. At this time, the player can only see the player's hat color at the adjacent vertex, and communication between players is not allowed. Once players are assigned hats, each player must guess the color of his hat at the same time. If at least one player guesses right, then they will win collectively. Given a graph GG, its hat guessing number HG(G)HG(G) is the largest integer qq such that there exists a guessing strategy guaranteeing at least one correct guess for any hat assignment of qq different colors. Let G(n,p)\mathcal{G}(n,p) denote the Erd\H{o}s-R\'{e}nyi random graphs with nn vertices and edge-chosen probability p(0,1) p\in(0,1). Alon-Chizewer and Bosek-Dudek-Farnik-Grytczuk-Mazur investigated the lower and upper bound for HG(G)HG(G) when GG(n,1/2)G\in \mathcal{G}(n,1/2), respectively. In this paper, we extends their results by showing that for any constant number pp, we have n1o(1)HG(G)(1o(1))nn^{1 - o(1)}\le HG(G) \le (1-o(1))n with high probability when GG(n,p)G\in \mathcal{G}(n,p).

Keywords

Cite

@article{arxiv.2302.04122,
  title  = {The hat guessing number of random graphs with constant edge-chosen probability},
  author = {Lanchao Wang and Yaojun Chen},
  journal= {arXiv preprint arXiv:2302.04122},
  year   = {2023}
}