English

On bounded degree graphs with large size-Ramsey numbers

Combinatorics 2023-07-25 v2

Abstract

The size-Ramsey number r^(G)\hat r(G') of a graph GG' is defined as the smallest integer mm so that there exists a graph GG with mm edges such that every 22-coloring of the edges of GG contains a monochromatic copy of GG'. Answering a question of Beck, Rodl and Szemeredi showed that for every n1n\geq 1 there exists a graph GG' on nn vertices each of degree at most three, with the size-Ramsey number at least cnlog160ncn\log^{\frac{1}{60}}n for a universal constant c>0c>0. In this note we show that a modification of Rodl and Szemeredi's construction leads to a bound r^(G)cnexp(clogn)\hat r(G')\geq cn\,\exp(c\sqrt{\log n}).

Keywords

Cite

@article{arxiv.2210.05818,
  title  = {On bounded degree graphs with large size-Ramsey numbers},
  author = {Konstantin Tikhomirov},
  journal= {arXiv preprint arXiv:2210.05818},
  year   = {2023}
}

Comments

revised version, accepted in Combinatorica

R2 v1 2026-06-28T03:22:57.656Z