Ohba’s Conjecture is True for Graphs with Independence Number 3
نویسنده
چکیده
Ohba’s conjecture states that if a graph G has chromatic number χ(G) = k and has at most 2k+1 vertices, then G has choice number Ch(G) equal to χ(G). We prove that Ohba’s conjecture is true for each graph that has independence number 3. We also prove that Ohba’s conjecture is true for each graph G that has an independent set S of size 4 such that G\S has independence number 3.
منابع مشابه
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تاریخ انتشار 2007