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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 {\epsilon}>0, sufficiently large prime number p and an arbitrary multiplicative subgroup R of the field Z/pZ, p^{\epsilon} < |R| < p^{2/3-{\epsilon}} the following holds |R + R|, |R - R| > |R|^{3/2+{\delta}}, where {\delta}>0 depends on {\epsilon} only.

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T. Schoen, I. D. Shkredov. 2010-08-04. On a question of Cochrane and Pinner concerning multiplicative subgroups. https://arxiv.org/abs/1008.0723

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