Affiliation:
1. School of Mathematics, Hohai University, Nanjing 211100, China
2. School of Mathematical Science, Nanjing Normal University, Nanjing 210046, China
Abstract
Let G be a graph. We denote the chromatic (clique) number of G by χ(G)(ω(G)). In this paper, we prove that (i) χ(G)≤2ω(G) if G is (P3∪P2, kite)-free, (ii) χ(G)≤ω2(G) if G is (P3∪P2, hammer)-free, (iii) χ(G)≤3ω2(G)+ω(G)2 if G is (P3∪P2,C5)-free. Furthermore, we also discuss the chromatic number of (P3∪P2,K4)-Free Graphs.
Funder
Natural Science Foundation of Jiangsu Province
Subject
General Mathematics,Engineering (miscellaneous),Computer Science (miscellaneous)
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