An upper bound for the number of perfect matchings in graphs
نویسنده
چکیده
We give an upper bound on the number of perfect matchings in an undirected simple graph G with an even number of vertices, in terms of the degrees of all the vertices in G. This bound is sharp if G is a union of complete bipartite graphs. This bound is a generalization of the upper bound on the number of perfect matchings in bipartite graphs on n + n vertices given by the Bregman-Minc inequality for the permanents of (0, 1) matrices. 2000 Mathematics Subject Classification: 05A15, 05C70.
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تاریخ انتشار 2008