Learn More
A graph G is said to be chromatic-choosable if ch(G)= (G). Ohba has conjectured that every graph G with 2 (G)+ 1 or fewer vertices is chromatic-choosable. It is clear that Ohba’s conjecture is true if and only if it is true for complete multipartite graphs. But for complete multipartite graphs, the graphs for which Ohba’s conjecture has been verified are(More)