Counting 1-Factors in Regular Bipartite Graphs
نویسنده
چکیده
perfect matchings. (A perfect matching or 1-factor is a set of disjoint edges covering all vertices.) This generalizes a result of Voorhoeve [11] for the case k = 3, stating that any 3-regular bipartite graph with 2n vertices has at least ( 4 3) n perfect matchings. The base in (1) is best possible for any k: let αk be the largest real number such that any k-regular bipartite graph with 2n vertices has at least (αk) n perfect matchings; then αk = (k−1) kk−2 . (2)
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 72 شماره
صفحات -
تاریخ انتشار 1998