Log-concavity for unimodal sequences
Number Theory
2023-07-12 v1 Combinatorics
Abstract
In this paper, we prove that the number of unimodal sequences of size is log-concave. These are coefficients of a mixed false modular form and have a Rademacher-type exact formula due to recent work of the second author and Nazaroglu on false theta functions. Log-concavity and higher Tur\'{a}n inequalities have been well-studied for (restricted) partitions and coefficients of weakly holomorphic modular forms, and analytic proofs generally require precise asymptotic series with error term. In this paper, we proceed from the exact formula for unimodal sequences to carry out this calculation. We expect our method applies to other exact formulas for coefficients of mixed mock/false modular objects.
Keywords
Cite
@article{arxiv.2307.05120,
title = {Log-concavity for unimodal sequences},
author = {Walter Bridges and Kathrin Bringmann},
journal= {arXiv preprint arXiv:2307.05120},
year = {2023}
}