Perfect couples of graphs
نویسندگان
چکیده
We., generalize the c~:mcept of perfect graphs in terms of additivity of a functional called graph entropy. The latter is an information theoretic functional on a graph G with a probability distribution P on its vertex set. For any fixed P it is .sub-additive with respect to graE._h union. The entropy of the complete graph equals the sum of those of G and its complement G iff G is perfect. We 'generalize this recent result to characterize all the cases when the sub-additivity of graph entropy holds with equality.
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ورودعنوان ژورنال:
- Combinatorica
دوره 12 شماره
صفحات -
تاریخ انتشار 1992