On the Sidon tails of $\left\{\lfloor x^n\rfloor\right\}$

Sayan Dutta

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arXiv · 2601.19807

On the Sidon tails of $\left\{\lfloor x^n\rfloor\right\}$

Sayan Dutta

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Abstract

We prove that the tail of the sets $$\mathbf S_x := \big\{\left\lfloor x^n\right\rfloor : n\in \mathbb N\big\}$$ are Sidon for almost all $x\in (1,2)$. Then we prove that for all $\varepsilon>0$, there exists $x\in (1,\, 1+\varepsilon)$ and $r\in (2-\varepsilon,\, 2)$ such that $\mathbf S_x$ and $\mathbf S_r$ do not have a Sidon tail.

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Sayan Dutta. 2026-01-27. On the Sidon tails of $\left\{\lfloor x^n\rfloor\right\}$. https://arxiv.org/abs/2601.19807

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