Small doubling in cyclic groups

Vsevolod F. Lev

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arXiv · 2010.03410

Small doubling in cyclic groups

Vsevolod F. Lev

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Abstract

We give a comprehensive description of the sets $A$ in finite cyclic groups such that $|2A|<\frac94|A|$; namely, we show that any set with this property is densely contained in a (one-dimensional) coset progression. This improves earlier results of Deshouillers-Freiman and Balasubramanian-Pandey.

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Vsevolod F. Lev. 2020-10-07. Small doubling in cyclic groups. https://arxiv.org/abs/2010.03410

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