On greene's theorem for digraphs
نویسندگان
چکیده
Greene's Theorem states that the maximum cardinality of an optimal k-path in a poset is equal to the minimum k-norm of a k-optimal coloring. This result was extended to all acyclic digraphs, and is conjectured to hold for general digraphs. We prove the result for general digraphs in which an optimal k-path contains a path of cardinality one. This implies the validity of the conjecture for all bipartite digraphs. We also extend Greene's Theorem to all split graphs. @ 1994 John Wiley & Sons, Inc.
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ورودعنوان ژورنال:
- Journal of Graph Theory
دوره 18 شماره
صفحات -
تاریخ انتشار 1994