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THE CHROMATIC NUMBER OF $\boldsymbol {(P_6,C_4,\mbox {diamond})}$-FREE GRAPHS

Published online by Cambridge University Press:  03 October 2022

KAIYANG LAN
Affiliation:
Center for Discrete Mathematics, Fuzhou University, Fujian 350003, PR China e-mail: kylan95@126.com
YIDONG ZHOU
Affiliation:
Center for Discrete Mathematics, Fuzhou University, Fujian 350003, PR China e-mail: zoed98@126.com
FENG LIU*
Affiliation:
Department of Mathematics, East China Normal University, Shanghai 200241, PR China

Abstract

The diamond is the complete graph on four vertices minus one edge; $P_n$ and $C_n$ denote the path and cycle on n vertices, respectively. We prove that the chromatic number of a $(P_6,C_4,\mbox {diamond})$-free graph G is no larger than the maximum of 3 and the clique number of G.

Type
Research Article
Copyright
© The Author(s), 2022. Published by Cambridge University Press on behalf of Australian Mathematical Publishing Association Inc.

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Footnotes

This research was partially supported by a grant from the National Natural Sciences Foundation of China (No. 11971111).

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