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arXiv · 1809.10908

Expansions at Cusps and Petersson Products in Pari/GP

Henri Cohen
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Abstract

We begin by explaining how to compute Fourier expansions at all cusps of any modular form of integral or half-integral weight thanks to a theorem of Borisov-Gunnells and explicit expansions of Eisenstein series at all cusps. Using this, we then give a number of methods for computing arbitrary Petersson products. All this is available in the current release of the Pari/GP package.

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Henri Cohen. 2018-09-28. Expansions at Cusps and Petersson Products in Pari/GP. https://arxiv.org/abs/1809.10908

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