On complete subgraphs of color-critical graphs
نویسندگان
چکیده
منابع مشابه
On complete subgraphs of color-critical graphs
A graph G is called k-critical if x(G) = k and x(G e) -C x(G) for each edge e of G, where x denotes the chromatic number. T. Gallai conjectured that every k-critical graph of order n contains at most n complete (k l)-subgraphs. In 1987, Stiebitz proved Gallai’s conjecture in the case k = 4, and in 1992 Abbott and Zhou proved Gallai’s conjecture for all k > 5. In their paper, Abbott and Zhou ask...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1995
ISSN: 0012-365X
DOI: 10.1016/0012-365x(94)00017-d