The harmonious coloring problem is NP-complete for interval and permutation graphs
نویسندگان
چکیده
منابع مشابه
The harmonious coloring problem is NP-complete for interval and permutation graphs
In this paper, we prove that the harmonious coloring problem is NP-complete for connected interval and permutation graphs. Given a simple graph G, a harmonious coloring of G is a proper vertex coloring such that each pair of colors appears together on at most one edge. The harmonious chromatic number is the least integer k for which G admits a harmonious coloring with k colors. Extending previo...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2007
ISSN: 0166-218X
DOI: 10.1016/j.dam.2007.07.005