A new upper bound for the chromatic number of a graph
نویسنده
چکیده
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.
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ورودعنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 27 شماره
صفحات -
تاریخ انتشار 2007