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arXiv · 2303.06850

Old and new results on the Furstenberg sets

Aihua Fan·Hervé Queffélec·Martine Quffélec
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Abstract

This paper is a complement to our previous paper [21]. It surveys the works on the Furstenberg set $S=\{2^{m}3^{n}: n\ge 0, m\ge 0\}$ and its random version $T$. We also present some new results. For example, it is proved that $T$ almost surely contains a subset of positive lower density which is $\frac{4}{3}$-Rider. It is also proved that a class of random sets of integers are Sidon sets when Bourgain's condition is not satisfied; this generalizes a result of Kahane-Katznelson. Some open questions about $S$ and $T$ are listed at the end of the paper.

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Aihua Fan, Hervé Queffélec, Martine Quffélec. 2023-03-13. Old and new results on the Furstenberg sets. https://arxiv.org/abs/2303.06850

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