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arXiv · 1008.0723

On a question of Cochrane and Pinner concerning multiplicative subgroups

T. Schoen·I. D. Shkredov
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Abstract

Answering a question of T. Cochrane and C. Pinner, we prove that for any ε>0, sufficiently large prime number p and an arbitrary multiplicative subgroup R of the field Z/pZ, p^ε < |R| < p^{2/3-ε} the following holds |R + R|, |R - R| > |R|^{3/2+δ}, where δ>0 depends on ε only.

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BibTeXRIS

T. Schoen, I. D. Shkredov. 2011-05-27. On a question of Cochrane and Pinner concerning multiplicative subgroups. https://arxiv.org/abs/1008.0723

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