English

Cop number of graphs without long holes

Combinatorics 2020-01-03 v1 Discrete Mathematics

Abstract

A hole in a graph is an induced cycle of length at least 4. We give a simple winning strategy for t-3 cops to capture a robber in the game of cops and robbers played in a graph that does not contain a hole of length at least t. This strengthens a theorem of Joret-Kaminski-Theis, who proved that t-2 cops have a winning strategy in such graphs. As a consequence of our bound, we also give an inequality relating the cop number and the Dilworth number of a graph.

Keywords

Cite

@article{arxiv.2001.00477,
  title  = {Cop number of graphs without long holes},
  author = {Vaidy Sivaraman},
  journal= {arXiv preprint arXiv:2001.00477},
  year   = {2020}
}

Comments

arXiv admin note: text overlap with arXiv:1903.01338

R2 v1 2026-06-23T13:01:28.307Z