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arXiv · 2512.22025

An elementary proof of some Ramanujan-type identities

M. A. Korolev
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Abstract

We give an elementary proof of some identities that express the squares of Riemann zeta function at integer points in terms of the series involving hyperbolic functions, digamma function, Bernoulli numbers etc. In this version, inaccuracies in the text have been corrected and one of the bibliographic references has been updated.

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M. A. Korolev. 2025-12-26. An elementary proof of some Ramanujan-type identities. https://arxiv.org/abs/2512.22025

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