Extremal graphs in some coloring problems
نویسندگان
چکیده
منابع مشابه
Extremal graphs in some coloring problems
For a simple graph G with chromatic number x(G), the Nordhaus-Gaddum inequalities give upper and lower bounds for z(G)•(G ¢) and z(G)+ x(GC). Based on a characterization by Fink of the extremal graphs G attaining the lower bounds for the product and sum, we characterize the extremal graphs G for which A(G)B(G c) is minimum, where A and B are each of chromatic number, achromatic number and pseud...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1998
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(97)00216-1