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arXiv · 0911.4261

An elementary proof of a Rodriguez-Villegas supercongruence

Roberto Tauraso
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Abstract

We give a short proof of the following known congruence: for every odd prime $p$ $$\sum_{k=0}^{p-1}{2k\choose k}^2 16^{-k}\equiv (-1)^{{p-1\over 2}}\pmod{p^2}.$$ Moreover, we provide some new results connected with the above congruence.

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Roberto Tauraso. 2009-11-22. An elementary proof of a Rodriguez-Villegas supercongruence. https://arxiv.org/abs/0911.4261

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