Sum coloring and interval graphs: a tight upper bound for the minimum number of colors
نویسندگان
چکیده
منابع مشابه
Coloring of trees with minimum sum of colors
The chromatic sum Σ(G) of a graph G is the smallest sum of colors among all proper colorings with natural numbers. The strength s(G) of G is the minimum number of colors needed to achieve the chromatic sum. We construct for each positive integer k a tree Tk with strength k that has maximum degree only 2k − 2. The result is best possible.
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2004
ISSN: 0012-365X
DOI: 10.1016/j.disc.2003.06.015