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arXiv · 2103.14670

On an application of higher energies to Sidon sets

Ilya D. Shkredov
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Abstract

We show that for any finite set $A$ and an arbitrary $\varepsilon>0$ there is $k=k(\varepsilon)$ such that the higher energy ${\mathsf{E}}_k(A)$ is at most $|A|^{k+\varepsilon}$ unless $A$ has a very specific structure. As an application we obtain that any finite subset $A$ of the real numbers or the prime field either contains an additive Sidon--type subset of size $|A|^{1/2+c}$ or a multiplicative Sidon--type subset of size $|A|^{1/2+c}$.

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Ilya D. Shkredov. 2021-03-26. On an application of higher energies to Sidon sets. https://arxiv.org/abs/2103.14670

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