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arXiv · 1905.02946

Note on Fourier expansions at cusps

François Brunault·Michael Neururer
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Abstract

This was originally an appendix to our paper `Fourier expansions at cusps' [arXiv:1807.00391]. The purpose of this note is to give a proof of a theorem of Shimura on the action of $\mathrm{Aut}(\mathbb{C})$ on modular forms for $Γ(N)$ from the perspective of algebraic modular forms. As the theorem is well-known, we do not intend to publish this note but want to keep it available as a preprint.

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François Brunault, Michael Neururer. 2019-05-08. Note on Fourier expansions at cusps. https://arxiv.org/abs/1905.02946

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