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arXiv · 1511.07221

Supercongruences on some binomial sums involving Lucas sequences

Guo-Shuai Mao·Hao Pan
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Abstract

In this paper, we confirm several conjectured congruences of Sun concerning the divisibility of binomial sums. For example, with help of a quadratic hypergeometric transformation, we prove that $$ \sum_{k=0}^{p-1}\binom{p-1}k\binom{2k}k^2\frac{P_k}{8^k}\equiv0\pmod{p^2} $$ for any prime $p\equiv 7\mod{8}$, where $P_k$ is the $k$-th Pell number. Further, we also propose three new congruences of the same type.

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Guo-Shuai Mao, Hao Pan. 2015-11-23. Supercongruences on some binomial sums involving Lucas sequences. https://doi.org/10.1016/j.jmaa.2016.10.055

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