2022/12/31 by Chen, Rong · 1 citation
#Combinatorics (math.CO) #FOS: Mathematics
paper · doi:10.48550/arxiv.2301.00112
For a number ℓ≥ 2, let Gℓ denote the family of graphs which have girth 2ℓ+1 and have no odd hole with length greater than 2ℓ+1. Plummer and Zha conjectured that every 3-connected and internally 4-connected graph in G2 is 3-colorable. Wu, Xu, and Xu conjectured that every graph in \bigcupℓ≥2Gℓ is 3-colorable. Chudnovsky et al. and Wu et al., respectively, proved that every graph in G2 and G3 is 3-colorable. In this paper, we prove that every graph in \bigcupℓ≥5Gℓ is 3-colorable.