The cost chromatic number and hypergraph parameters
نویسندگان
چکیده
In a graph, by definition, the weight of a (proper) coloring with positive integers is the sum of the colors. The chromatic sum is the minimum weight, taken over all the proper colorings. The minimum number of colors in a coloring of minimum weight is the cost chromatic number or strength of the graph. We derive general upper bounds for the strength, in terms of a new parameter of representations by edge intersections of hypergraphs.
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ورودعنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 26 شماره
صفحات -
تاریخ انتشار 2006