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arXiv · 2003.14221

On a supercongruence conjecture of Z.-W. Sun

Guo-Shuai Mao
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Abstract

In this paper, we partly prove a supercongruence conjectured by Z.-W. Sun in 2013. Let $p$ be an odd prime and let $a\in\mathbb{Z}^{+}$. Then if $p\equiv1\pmod3$, we have \begin{align*} \sum_{k=0}^{\lfloor\frac{5}6p^a\rfloor}\frac{\binom{2k}k}{16^k}\equiv\left(\frac{3}{p^a}\right)\pmod{p^2}, \end{align*} where $\left(\frac{\cdot}{\cdot}\right)$ is the Jacobi symbol.

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Guo-Shuai Mao. 2020-03-30. On a supercongruence conjecture of Z.-W. Sun. https://doi.org/10.1007/s11401-022-0332-7

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