English

Strongly common graphs with odd girth are cycles

Combinatorics 2023-05-19 v1

Abstract

A graph HH is called strongly common if for every coloring ϕ\phi of KnK_n with two colors, the number of monochromatic copies of HH is at least the number of monochromatic copies of HH in a random coloring of KnK_n with the same density of color classes as ϕ\phi. In this note we prove that if a graph has odd girth but is not a cycle, then it is not strongly common. This answers a question of Chen and Ma.

Keywords

Cite

@article{arxiv.2305.10903,
  title  = {Strongly common graphs with odd girth are cycles},
  author = {Leo Versteegen},
  journal= {arXiv preprint arXiv:2305.10903},
  year   = {2023}
}

Comments

3 pages

R2 v1 2026-06-28T10:38:08.622Z