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 impl
A Combinatorial Proof of the Log-Concavity of the Numbers of Permutations with k Runs
✍ Scribed by Miklós Bóna; Richard Ehrenborg
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 178 KB
- Volume
- 90
- Category
- Article
- ISSN
- 0097-3165
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