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arXiv · 2406.03275

Improved stability for the size and structure of sumsets

Andrew Granville·Jack Smith·Aled Walker
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Abstract

Let $A \subset \mathbb{Z}^d$ be a finite set. It is known that the sumset $NA$ has predictable size ($\vert NA\vert = P_A(N)$ for some $P_A(X) \in \mathbb{Q}[X]$) and structure (all of the lattice points in some finite cone other than all of the lattice points in a finite collection of exceptional subcones), once $N$ is larger than some threshold. In previous work, joint with Shakan, the first and third named authors established the first effective bounds for both of these thresholds for an arbitrary set $A$. In this article we substantially improve each of these bounds, coming much closer to the corresponding lower bounds known.

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Andrew Granville, Jack Smith, Aled Walker. 2024-06-05. Improved stability for the size and structure of sumsets. https://arxiv.org/abs/2406.03275

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