($P_2+P_4$, $K_4-e$)-free graphs are nearly $\omega$-colorable
Abstract
For a graph , and respectively denote the chromatic number and clique number of . In this paper, we show the following results: (i) If is a (, )-free graph with , then , and the bound is tight for each . (ii) If is a (, )-free graph with , then . These results extend the chromatic bounds known for the class of (, )-free graphs and for the class of (, )-free graphs, improve the bound of Chen and Zhang [arXiv:2412.14524 [math.CO], 2024] given for the class of (, )-free graphs, partially answer a question of Ju and the third author [Theor. Comp. Sci. 993 (2024) Article No.: 114465] on `near optimal colorable graphs', and a question of Schiermeyer (unpublished) on the chromatic bound for (, )-free graphs.
Cite
@article{arxiv.2501.02543,
title = {($P_2+P_4$, $K_4-e$)-free graphs are nearly $\omega$-colorable},
author = {C. U. Angeliya and T. Karthick and Shenwei Huang},
journal= {arXiv preprint arXiv:2501.02543},
year = {2025}
}
Comments
Revised version includes the new result for the case Omega(G)=4