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arXiv · 2212.09455

On congruences involving Ap\'ery numbers

Wei Xia·Zhi-Wei Sun
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Abstract

In this paper, we mainly establish a congruence for a sum involving Ap\'{e}ry numbers, which was conjectured by Z.-W. Sun. Namely, for any prime $p>3$ and positive odd integer $m$, we prove that there is a $p$-adic integer $c_m$ only depending on $m$ such that $$\sum_{k=0}^{p-1}(2k+1)^{m}(-1)^kA_k\equiv c_mp\left(\frac{p}{3}\right)\pmod{p^3},$$ where $A_k=\sum_{j=0}^{k}\binom{k}{j}^2\binom{k+j}{j}^2$ is the Ap\'{e}ry number and $(\frac{\cdot}{p})$ is the Legendre symbol.

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Wei Xia, Zhi-Wei Sun. 2022-12-19. On congruences involving Ap\'ery numbers. https://arxiv.org/abs/2212.09455

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