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arXiv · 2604.08930

Linear recurrence sequences and palindromic concatenations of two repdigits in base $\beta$

Ruofan Li
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Abstract

Let $\beta$ be a non-unit real algebraic integer greater than one and $\{a_{n}\}_{n \geq 0}$ be a sequence satisfying a linear recurrence relation $a_{n+3}=aa_{n+2}+ba_{n+1}+ca_{n}$. Under certain conditions, we prove that the number of $a_{n}$ which are palindromic concatenations of two repdigits in base $\beta$ is finite.

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Ruofan Li. 2026-04-10. Linear recurrence sequences and palindromic concatenations of two repdigits in base $\beta$. https://arxiv.org/abs/2604.08930

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