Log-concavity, the Ulam distance and involutions
Combinatorics
2015-02-20 v1
Abstract
We prove that in a large collection of naturally defined sets of permutations of fixed length, the numbers of permutations at Ulam distance k from the identity form a log-concave sequence in k.
Cite
@article{arxiv.1502.05438,
title = {Log-concavity, the Ulam distance and involutions},
author = {Miklós Bóna and Marie-Louise Bruner},
journal= {arXiv preprint arXiv:1502.05438},
year = {2015}
}
Comments
17 pages