A shifted convolution sum for $GL(3)\times GL(2)$

Ping Xi

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arXiv · 1703.08891

A shifted convolution sum for $GL(3)\times GL(2)$

Ping Xi

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Abstract

In this paper, we estimate the shifted convolution sum \[\sum_{n\geqslant1}\lambda_1(1,n)\lambda_2(n+h)V\Big(\frac{n}{X}\Big),\] where $V$ is a smooth function with support in $[1,2]$, $1\leqslant|h|\leqslant X$, $\lambda_1(1,n)$ and $\lambda_2(n)$ are the $n$-th Fourier coefficients of $SL(3,\mathbf{Z})$ and $SL(2,\mathbf{Z})$ Hecke-Maass cusp forms, respectively. We prove an upper bound $O(X^{\frac{21}{22}+\varepsilon})$, updating a recent result of Munshi.

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Ping Xi. 2017-03-27. A shifted convolution sum for $GL(3)\times GL(2)$. https://arxiv.org/abs/1703.08891

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