English

On a conjecture of Andrews and Bachraoui

Number Theory 2026-01-08 v1

Abstract

Recently, Andrews and Bachraoui considered a generating function Fk,m(q)F_{k,m}(q) associated with certain two-color partitions, and conjectured that this function has non-negative coefficients for m=1m=1. They showed this property for 1k41 \leq k \leq 4. In this note, we prove that Fk,1(q)F_{k,1}(q) has non-negative coefficients for 5k105 \leq k \leq 10. Moreover, we show that, as kk\to\infty, Fk,1(q)F_{k,1}(q) is related to Ramanujan's third order mock theta function ω(q)\omega(q) and to quotients of certain qq-binomial coefficients.

Keywords

Cite

@article{arxiv.2601.04014,
  title  = {On a conjecture of Andrews and Bachraoui},
  author = {Koustav Banerjee and Kathrin Bringmann and William J. Keith},
  journal= {arXiv preprint arXiv:2601.04014},
  year   = {2026}
}