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arXiv · 2507.12906

Thabit and Williams Numbers Base $b$ as a Sum or Difference of Two $g$-Repdigits

Kouèssi Norbert Adédji·Marija Bliznac Trebješanin·Jelena Pleština
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Abstract

We investigate cases where Thabit and Williams numbers in base $b$ can be expressed as the sum or difference of two $g$-repdigits. For specific values of $b$ and $g$, we describe parametric solutions yielding infinitely many solutions for some equations and establish upper bounds for the parameters of the remaining finitely many solutions. As an illustration, we also provide a complete solution for some equations.

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Kouèssi Norbert Adédji, Marija Bliznac Trebješanin, Jelena Pleština. 2025-07-17. Thabit and Williams Numbers Base $b$ as a Sum or Difference of Two $g$-Repdigits. https://arxiv.org/abs/2507.12906

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