Extending the Greene-Kleitman Theorem to Directed Graphs
نویسنده
چکیده
The celebrated Dilworth theorem (Ann. of Math. 5 1 (1950), 161-166) on the decomposition of finite posets was extended by Greene and Kleitman (J. Combin. Theory Ser. A 20 (1976), 41-68). Using the Gallai-Milgram theorem (Acta Sci. Math. 2 1 (1960), 18 l-186) we prove a theorem on acyclic digraphs which contains the Greene-Kleitman theorem. The method of proof is derived from M. Saks’ elegant proof (Adv. in Math. 33 (1979), 207-211) of the Greene-Kleitman theorem.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 30 شماره
صفحات -
تاریخ انتشار 1981