English

Graphs with girth $2\ell+1$ and without longer odd holes are $3$-colorable

Combinatorics 2023-01-03 v1

Abstract

For a number 2\ell\geq 2, let G\mathcal{G}_{\ell} denote the family of graphs which have girth 2+12\ell+1 and have no odd hole with length greater than 2+12\ell+1. Plummer and Zha conjectured that every 3-connected and internally 4-connected graph in G2\mathcal{G}_2 is 3-colorable. Wu, Xu, and Xu conjectured that every graph in 2G\bigcup_{\ell\geq2}\mathcal{G}_{\ell} is 3-colorable. Chudnovsky et al. and Wu et al., respectively, proved that every graph in G2\mathcal{G}_2 and G3\mathcal{G}_3 is 3-colorable. In this paper, we prove that every graph in 5G\bigcup_{\ell\geq5}\mathcal{G}_{\ell} is 3-colorable.

Keywords

Cite

@article{arxiv.2301.00112,
  title  = {Graphs with girth $2\ell+1$ and without longer odd holes are $3$-colorable},
  author = {Rong Chen},
  journal= {arXiv preprint arXiv:2301.00112},
  year   = {2023}
}

Comments

arXiv admin note: text overlap with arXiv:2210.12376