English

$\alpha$-chromatic symmetric functions

Combinatorics 2025-04-21 v2

Abstract

In this paper, we introduce the \emph{α\alpha-chromatic symmetric functions} χπ(α)[X;q]\chi^{(\alpha)}_\pi[X;q], extending Shareshian and Wachs' chromatic symmetric functions with an additional real parameter α\alpha. We present positive combinatorial formulas with explicit interpretations. Notably, we show an explicit monomial expansion in terms of the α\alpha-binomial basis and an expansion into certain chromatic symmetric functions in terms of the α\alpha-falling factorial basis. Among various connections with other subjects, we highlight a significant link to qq-rook theory, including a new solution to the qq-hit problem posed by Garsia and Remmel in their 1986 paper introducing qq-rook polynomials.

Keywords

Cite

@article{arxiv.2407.06965,
  title  = {$\alpha$-chromatic symmetric functions},
  author = {Jim Haglund and Jaeseong Oh and Meesue Yoo},
  journal= {arXiv preprint arXiv:2407.06965},
  year   = {2025}
}

Comments

Minor corrections

R2 v1 2026-06-28T17:34:31.199Z