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arXiv · 2607.24867

Ramanujan-Type Series of Signature 2: Analytical Evaluation via Degree-2 Modular Transformations

Pablo Fernández Refolio
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Abstract

We provide an explicit analytical evaluation of Ramanujan-type series for $1/\pi$ of signature 2. Focusing on the singular moduli $k_{r}$ for $r \in \{2, 3, 4, 7\}$, we demonstrate that the underlying elliptic identities can be established through modular transformations of degree 2.

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Pablo Fernández Refolio. 2026-07-26. Ramanujan-Type Series of Signature 2: Analytical Evaluation via Degree-2 Modular Transformations. https://arxiv.org/abs/2607.24867

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