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arXiv · 2508.09750

Large values of character sums with multiplicative coefficients

Zikang Dong·Zhonghua Li·Yutong Song·Shengbo Zhao
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Abstract

In this article, we investigate large values of Dirichlet character sums with multiplicative coefficients $\sum_{n\le N}f(n)\chi(n)$. We prove an Omega result in the region $\exp((\log q)^{\frac12+\varepsilon})\le N\le\sqrt q$, where $q$ is the prime modulus.

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Zikang Dong, Zhonghua Li, Yutong Song, Shengbo Zhao. 2025-08-13. Large values of character sums with multiplicative coefficients. https://arxiv.org/abs/2508.09750

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