منابع مشابه
Flipping Triangles and Rectangles
For any graph G, it is obvious that χ(G) ≥ ω(G), but whether χ(G) can be bounded from above by a function of ω(G) is not at all clear. Recall that the two numbers are equal for every induced subgraph of a perfect graph. Thus the ratio of the chromatic number to the clique number of a graph is often studied as a measure of its “imperfection”; see for example Dumitrescu and Jiang (2010) for some ...
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ژورنال
عنوان ژورنال: Journal of the Royal Society of Medicine
سال: 2001
ISSN: 0141-0768,1758-1095
DOI: 10.1177/014107680109400901