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arXiv · 2304.12572

A twisted additive divisor problem

Alex Cowan
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Abstract

We give asymptotics for shifted convolutions of the form $$\sum_{n < X} \frac{\sigma_{2u}(n,\chi)\sigma_{2v}(n+k,\psi)}{n^{u+v}}$$ for nonzero complex numbers $u,v$ and nontrivial Dirichlet characters $\chi,\psi$. We use the technique of "automorphic regularization" to find the spectral decomposition of a combination of Eisenstein series which is not obviously square-integrable. The error term we obtain is in some cases smaller than what the method we use typically yields.

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Alex Cowan. 2023-04-25. A twisted additive divisor problem. https://arxiv.org/abs/2304.12572

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