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arXiv · 2103.00649

The index of $\mathbb{T}^{\text{an}}$ in $\mathbb{T}$

Noah Taylor
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Abstract

For a prime level $N$, we compute the index of the anemic Hecke algebra of weight 2 level $\Gamma_0(N)$ forms inside the full Hecke algebra. We prove that the index is fully described by the presence of weight 1 Katz forms of the same level.

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Noah Taylor. 2021-02-28. The index of $\mathbb{T}^{\text{an}}$ in $\mathbb{T}$. https://arxiv.org/abs/2103.00649

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