English

Acyclic List Colouring Locally Planar Graphs

Combinatorics 2024-12-13 v1

Abstract

A (vertex) colouring of graph is \emph{acyclic} if it contains no bicoloured cycle. In 1979, Borodin proved that planar graphs are acyclically 5-colourable. In 2010, Kawarabayashi and Mohar proved that locally planar graphs are acyclically 7-colourable. In 2002, Borodin, Fon-Der-Flaass, Kostochka, Raspaud, and Sopena proved that planar graphs are acyclically 7-list-colourable. We prove that locally planar graphs are acyclically 9-list-colourable\textemdash no bound for acyclic list colouring locally planar graphs for any fixed number of colours was previously known.

Keywords

Cite

@article{arxiv.2412.09410,
  title  = {Acyclic List Colouring Locally Planar Graphs},
  author = {Luke Postle and Evelyne Smith-Roberge and Massimo Vicenzo},
  journal= {arXiv preprint arXiv:2412.09410},
  year   = {2024}
}

Comments

19 pages, 4 figures

R2 v1 2026-06-28T20:32:41.597Z