English

Chordal directed graphs are not $\chi$-bounded

Combinatorics 2022-02-03 v1

Abstract

We show that digraphs with no transitive tournament on 33 vertices and in which every induced directed cycle has length 33 can have arbitrarily large dichromatic number. This answers to the negative a question of Carbonero, Hompe, Moore, and Spirkl (and extends some of their results).

Cite

@article{arxiv.2202.01006,
  title  = {Chordal directed graphs are not $\chi$-bounded},
  author = {Pierre Aboulker and Nicolas Bousquet and Rémi de Verclos},
  journal= {arXiv preprint arXiv:2202.01006},
  year   = {2022}
}
R2 v1 2026-06-24T09:15:38.650Z