English

Distant 2-Colored Components on Embeddings Part II: The Short-Inseparable Case

Combinatorics 2024-03-22 v2

Abstract

This is the second in a sequence of three papers in which we prove the following generalization of Thomassen's 5-choosability theorem: Let GG be a graph embedded on a surface of genus gg. Then GG can be LL-colored, where LL is a list-assignment for GG in which every vertex has a 5-list except for a collection of pairwise far-apart components, each precolored with an ordinary 2-coloring, as long as the face-width of GG is at least 2Ω(g)2^{\Omega(g)} and the precolored components are of distance at least 2Ω(g)2^{\Omega(g)} apart. This provides an affirmative answer to a generalized version of a conjecture of Thomassen and also generalizes a result from 2017 of Dvo\v{r}\'ak, Lidick\'y, Mohar, and Postle about distant precolored vertices. In this paper we prove that the above result holds for a restricted class of embeddings, i.e. those embeddings which satisfy certain triangulation conditions and do not have separating cycles of length at most four.

Keywords

Cite

@article{arxiv.2212.10506,
  title  = {Distant 2-Colored Components on Embeddings Part II: The Short-Inseparable Case},
  author = {Joshua Nevin},
  journal= {arXiv preprint arXiv:2212.10506},
  year   = {2024}
}

Comments

64 pages

R2 v1 2026-06-28T07:45:19.281Z