English

Cops and robbers on $P_5$-free graphs

Combinatorics 2025-10-29 v1 Discrete Mathematics

Abstract

We prove that every connected P5P_5-free graph has cop number at most two, solving a conjecture of Sivaraman. In order to do so, we first prove that every connected P5P_5-free graph GG with independence number at least three contains a three-vertex induced path with vertices a-b-ca \hbox{-} b \hbox{-} c in order, such that every neighbour of cc is also adjacent to one of a,ba,b.

Keywords

Cite

@article{arxiv.2301.13175,
  title  = {Cops and robbers on $P_5$-free graphs},
  author = {Maria Chudnovsky and Sergey Norin and Paul Seymour and Jérémie Turcotte},
  journal= {arXiv preprint arXiv:2301.13175},
  year   = {2025}
}

Comments

14 pages

R2 v1 2026-06-28T08:27:17.661Z