文摘
As a natural generalization of graph coloring, Vinceintroduced the star chromatic number of a graphG and denoted it by$
\chi {\left( G \right)} \geqslant \frac{{n + 3}}
{2}
$
\chi {\left( G \right)} \geqslant \frac{{n + 3}}
{2}
, thenc(M(G))=(M(G)). Let S be the set of vertices of degreen–1 inG. It is proved that if|S| 3, thenc(M(G))=(M(G)), and if |S| 5, then c(M2(G))=(M2(G)), which implies the known results ofChang, Huang, and Zhu that if n3, c(M(Kn))=(M(Kn)), and ifn5, thenc(M2(Kn))=(M2(Kn)).