English

Ramsey numbers of trees

Combinatorics 2025-09-10 v1

Abstract

We show that there exists a constant c>0c>0 such that every nn-vertex tree TT with Δ(T)cn\Delta(T)\le cn has Ramsey number R(T)=max{t1+2t2,2t1}1R(T)=\max\{t_1+2t_2,2t_1\}-1, where t1t2t_1\ge t_2 are the sizes of the bipartition classes of TT. This improves an asymptotic result of Haxell, {\L}uczak, and Tingley from 2002, and shows that, though Burr's 1974 conjecture on the Ramsey numbers of trees has long been known to be false for certain `double stars', it is true for trees with up to small linear maximum degree.

Keywords

Cite

@article{arxiv.2509.07934,
  title  = {Ramsey numbers of trees},
  author = {Richard Montgomery and Matías Pavez-Signé and Jun Yan},
  journal= {arXiv preprint arXiv:2509.07934},
  year   = {2025}
}

Comments

59 pages, 22 figures

R2 v1 2026-07-01T05:28:47.072Z