Cycles of given length in oriented graphs
نویسندگان
چکیده
The Caccetta-Häggkvist conjecture would determine the minimum outdegree which forces a cycle of length at most k in an oriented graph. We study the related question of which minimum outand indegree forces a cycle of length exactly k in an oriented graph. We answer this question whenever k is not a multiple of 3 and propose a conjecture for the other cases.
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عنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 100 شماره
صفحات -
تاریخ انتشار 2010