On the fractional chromatic number and the lexicographic product of graphs
نویسندگان
چکیده
منابع مشابه
On the fractional chromatic number and the lexicographic product of graphs
For graphs G and H let GH] be their lexicographic product and let f (G) = inff(GK n ])=n j n = 1; 2; : : :g be the fractional chromatic number of G. For n 1 set G n = fG j (GK n ]) = nn(G)g. Then lim n!1 G n = fG j f (G) = (G)g: Moreover, we prove that for any n 2 the class G n forms a proper subclass of G n?1. As a by-product we show that if G is a-extremal, vertex transitive graph on (G)(G) ?...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1998
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(97)00212-4