English

Schur log-concavity and the quantum Pascal triangle

Combinatorics 2025-09-29 v1

Abstract

We say a sequence f0,f1,f2,f_0, f_1, f_2, \ldots of symmetric functions is Schur log-concave if fn2fn1fn+1f_n^2 - f_{n-1}f_{n+1} is Schur positive for all n1n\ge1. We conjecture that a very general class of sequences of Schur functions satisfies this property, and show it for sequences of Schur functions indexed by partitions with growing first part and column. Our findings are related to work of Lam, Postnikov and Pylyavskyy on Schur positivity, and of Butler, Sagan, and the second author on qq-log-concavity.

Keywords

Cite

@article{arxiv.2509.22648,
  title  = {Schur log-concavity and the quantum Pascal triangle},
  author = {Álvaro Gutiérrez and Christian Krattenthaler},
  journal= {arXiv preprint arXiv:2509.22648},
  year   = {2025}
}

Comments

14 pages, 2 figures

R2 v1 2026-07-01T05:59:22.136Z