English

On $(p,q)$-binomial coefficient ratios for complex parameters

Classical Analysis and ODEs 2026-07-09 v1 Combinatorics

Abstract

We prove local asymptotics for near-central complex (p,q)(p,q)-binomial coefficient moduli ratios allowing an imaginary parameter perturbation of order n3/4n^{-3/4} at a n\sqrt{n} length scale from the centre. Moreover, we obtain ratio asymptotics for a smaller imaginary perturbation of order n5/4n^{-5/4} at the length scale n3/4n^{3/4}. These results were obtained by reducing the two-parameter coefficients to just one parameter, giving a branch-free logarithmic representation of the second-order ratio and, hence, uniform complex curvature asymptotes for near-central ratios.

Cite

@article{arxiv.2607.08163,
  title  = {On $(p,q)$-binomial coefficient ratios for complex parameters},
  author = {Per Åhag and Rafał Czyż and Per-Håkan Lundow},
  journal= {arXiv preprint arXiv:2607.08163},
  year   = {2026}
}