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arXiv · 1904.08234

Subsets of $\mathbb{F}^*_p$ with only small products or ratios

Patrick Letendre
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Abstract

Let $p$ be a fixed prime. We estimate the number of elements of a set $A \subseteq \mathbb{F}^*_p$ for which $$ s_1s_2 \equiv a \pmod{p} \quad \mbox{for some}\quad a \in [-X,X] \quad \mbox{for all}\quad s_1,s_2 \in A. $$ We also consider variations and generalizations.

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Patrick Letendre. 2019-04-17. Subsets of $\mathbb{F}^*_p$ with only small products or ratios. https://arxiv.org/abs/1904.08234

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