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Combinatorial Proof of the Log-Concavity of the Sequence of Matching Numbers

✍ Scribed by C. Krattenthaler


Publisher
Elsevier Science
Year
1996
Tongue
English
Weight
145 KB
Volume
74
Category
Article
ISSN
0097-3165

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✦ Synopsis


For k l we construct an injection from the set of pairs of matchings in a given graph G of sizes l&1 and k+1 into the set of pairs of matchings in G of sizes l and k. This provides a combinatorial proof of the log-concavity of the sequence of matching numbers of a graph. Besides, this injection implies that a certain weighted version of the matching numbers is strongly x-log-concave in the sense of Sagan (Discrete Math. 99 (1992), 289 306).


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