On Feedback Vertex Sets in Tournaments
نویسندگان
چکیده
A tournament T is an orientation of a complete graph, and a feedback vertex set of T is a subset of vertices intersecting every directed cycle of T . We prove that every tournament on n vertices has at most 1.6740 minimal feedback vertex sets and some tournaments have 1.5448 minimal feedback vertex sets. This improves a result by Moon (1971) who showed upper and lower bounds of 1.7170 and 1.4757 on the maximum number of minimal feedback vertex sets in tournaments.
منابع مشابه
Feedback Vertex Sets in Tournaments
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ورودعنوان ژورنال:
- CoRR
دوره abs/0905.0567 شماره
صفحات -
تاریخ انتشار 2009