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arXiv · 0801.2256

On the Number of Matchings in Regular Graphs

S. Friedland·E. Krop·K. Markström
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Abstract

For the set of graphs with a given degree sequence, consisting of any number of $2's$ and $1's$, and its subset of bipartite graphs, we characterize the optimal graphs who maximize and minimize the number of $m$-matchings. We find the expected value of the number of $m$-matchings of $r$-regular bipartite graphs on $2n$ vertices with respect to the two standard measures. We state and discuss the conjectured upper and lower bounds for $m$-matchings in $r$-regular bipartite graphs on $2n$ vertices, and their asymptotic versions for infinite $r$-regular bipartite graphs. We prove these conjectures for 2-regular bipartite graphs and for $m$-matchings with $m\le 4$.

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S. Friedland, E. Krop, K. Markström. 2008-01-15. On the Number of Matchings in Regular Graphs. https://arxiv.org/abs/0801.2256

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