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arXiv · 2502.08760

Modular Forms and Certain ${}_2F_1(1)$ Hypergeometric Series

Esme Rosen
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Abstract

Using the framework relating hypergeometric motives to modular forms, we define an explicit family of weight 2 Hecke eigenforms with complex multiplication. We use the theory of ${}_2F_1(1)$ hypergeometric series and Ramanujan's theory of alternative bases to compute the exact central $L$-value of these Hecke eigenforms in terms of special beta values. We also show the integral Fourier coefficients can be written in terms of Jacobi sums, reflecting a motivic relation between the hypergeometric series and the modular forms.

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Esme Rosen. 2025-02-12. Modular Forms and Certain ${}_2F_1(1)$ Hypergeometric Series. https://arxiv.org/abs/2502.08760

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