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arXiv · 2405.12662

An $L^2$-bound for the Barban-Vehov weights

Olivier Ramaré·Sebastian Zuniga Alterman
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Abstract

Let $\lambda$ the Barban--Vehov weights, defined in $(1)$. Let $X\ge z_1\ge100$ and $z_2=z_1^\tau$ for some $\tau>1$. We prove that \begin{equation*} \sum_{n\le X}\frac{1}{n}\Bigl(\sum_{\substack{d|n}}\lambda_d\Bigr)^2 \le f(\tau)\frac{\log X}{\log (z_2/z_1)}, \end{equation*} for a completely determined function $f:(1,\infty)\to\mathbb{R}_{>0}$. In particular, we may take $f(2)=30$, saving more than a factor of $5$ on what was the best known result for $\tau=2$. Two related estimates are also provided for general $\tau>1$.

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Olivier Ramaré, Sebastian Zuniga Alterman. 2024-05-21. An $L^2$-bound for the Barban-Vehov weights. https://doi.org/10.7169/facm%2F241018-19-5

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