English

$q$-Derivative Grammar

Combinatorics 2026-04-28 v1

Abstract

The concept of context-free grammar in Combinatorics was first introduced by Chen in 1993. In 1996, Dumont significantly extended the theory of context-free grammars to a variety of other combinatorial models. Substantial progress in this direction has been achieved over the last decade. In this paper, we introduce a qq-analogue of context-free grammars, which we call the qq-derivative grammar. We establish the basic framework of qq-grammars and develop the qq-grammar calculus for computing qq-exponential generating functions associated with qq-grammars. Concrete qq-grammars are constructed to study qq-Eulerian, qq-Roselle and qq-Andr\'e polynomials, including their generating functions and recurrences. This work extends the grammatical method to the qq-setting and opens up new research directions.

Cite

@article{arxiv.2604.23959,
  title  = {$q$-Derivative Grammar},
  author = {Guo-Niu Han and Kathy Q. Ji and Huan Xiong},
  journal= {arXiv preprint arXiv:2604.23959},
  year   = {2026}
}

Comments

66 pages, 8 figures

R2 v1 2026-07-01T12:36:12.870Z