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arXiv · 2007.04859

Character sums over affine spaces and applications

Lucas Reis
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Abstract

Given a finite field $\mathbb F_q$, a positive integer $n$ and an $\mathbb F_q$-affine space $\mathcal A\subseteq \mathbb F_{q^n}$, we provide a new bound on the sum $\sum_{a\in \mathcal A}\chi(a)$, where $\chi$ a multiplicative character of $\mathbb F_{q^n}$. We focus on the applicability of our estimate to results regarding the existence of special primitive elements in $\mathbb F_{q^n}$. In particular, we obtain substantial improvements on previous works.

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Lucas Reis. 2020-07-09. Character sums over affine spaces and applications. https://arxiv.org/abs/2007.04859

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