English

Supercongruences for sums involving Domb numbers

Number Theory 2020-08-18 v2 Combinatorics

Abstract

We prove some supercongruence and divisibility results on sums involving Domb numbers, which confirm four conjectures of Z.-W. Sun and Z.-H. Sun. For instance, by using a transformation formula due to Chan and Zudilin, we show that for any prime p5p\ge 5, \begin{align*} \sum_{k=0}^{p-1}\frac{3k+1}{(-32)^k}{\rm Domb}(k)\equiv (-1)^{\frac{p-1}{2}}p+p^3E_{p-3} \pmod{p^4}, \end{align*} which is regarded as a pp-adic analogue of the following interesting formula for 1/π1/\pi due to Rogers: \begin{align*} \sum_{k=0}^{\infty}\frac{3k+1}{(-32)^k}{\rm Domb}(k)=\frac{2}{\pi}. \end{align*} Here Domb(n){\rm Domb}(n) and EnE_n are the famous Domb numbers and Euler numbers.

Keywords

Cite

@article{arxiv.2008.02647,
  title  = {Supercongruences for sums involving Domb numbers},
  author = {Ji-Cai Liu},
  journal= {arXiv preprint arXiv:2008.02647},
  year   = {2020}
}

Comments

11 pages

R2 v1 2026-06-23T17:40:56.811Z