A new upper bound for the chromatic number of a graph
Ingo Schiermeyer
Discussiones Mathematicae Graph Theory, Tome 27 (2007), p. 137-142 / Harvested from The Polish Digital Mathematics Library
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Let G be a graph of order n with clique number ω(G), chromatic number χ(G) and independence number α(G). We show that χ(G) ≤ [(n+ω+1-α)/2]. Moreover, χ(G) ≤ [(n+ω-α)/2], if either ω + α = n + 1 and G is not a split graph or α + ω = n - 1 and G contains no induced Kω+3-C₅.

Publié le : 2007-01-01
EUDML-ID : urn:eudml:doc:270707 
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Ingo Schiermeyer. A new upper bound for the chromatic number of a graph. Discussiones Mathematicae Graph Theory, Tome 27 (2007) pp. 137-142. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1350/

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