Combinatorial Proof of the Log-Concavity of the Sequence of Matching Numbers
β Scribed by C. Krattenthaler
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 145 KB
- Volume
- 74
- Category
- Article
- ISSN
- 0097-3165
No coin nor oath required. For personal study only.
β¦ 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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