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arXiv · 2210.00926

Members of Narayana's cow sequence that are concatenations of two repdigits

Mahadi Ddamulira·Paul Emong·Geoffrey Ismail Mirumbe
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Abstract

Let $ (N_n)_{n\ge 0}$ be the Narayana's cow sequence defined by a third-order recurrence relation $ N_0=0,\ N_1= N_2=1 $, and $ N_{n+3}=N_{n+2}+N_n $ for all $ n\ge 0 $. In this paper, we determine all Narayana numbers that are concatenations of two repdigits. The proof of our main theorem uses lower bounds for linear forms in logarithms and a version of the Baker-Davenport reduction method in Diophantine approximation.

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Mahadi Ddamulira, Paul Emong, Geoffrey Ismail Mirumbe. 2022-10-03. Members of Narayana's cow sequence that are concatenations of two repdigits. https://arxiv.org/abs/2210.00926

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