The Ratio Monotonicity of the $q$-Derangement Numbers
Combinatorics
2007-10-04 v3
Abstract
We show that the -derangement numbers satisfy a ratio monotone property, which is analogous to the log-concavity and is stronger than the spiral property and the unimodality.
Keywords
Cite
@article{arxiv.0708.2572,
title = {The Ratio Monotonicity of the $q$-Derangement Numbers},
author = {William Y. C. Chen and Ernest X. W. Xia},
journal= {arXiv preprint arXiv:0708.2572},
year = {2007}
}
Comments
16 pages. log-concavity possibly except for one term is added as a corollary