On the fractional chromatic number, the chromatic number, and graph products
نویسندگان
چکیده
منابع مشابه
On the fractional chromatic number, the chromatic number, and graph products
It is shown that the difference between the chromatic number χ and the fractional chromatic number χf can be arbitrarily large in the class of uniquely colorable, vertex transitive graphs. For the lexicographic product G ◦ H it is shown that χ(G ◦ H) ≥ χf (G)χ(H). This bound has several consequences, in particular it unifies and extends several known lower bounds. Lower bounds of Stahl (for gen...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2002
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(01)00312-0