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On the size of the intersection of two Lucas sequences of distinct type II

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Abstract

Let a and b be positive integers, with a not perfect square and b > 1. Recently, He, Togbé and Walsh proved that the Diophantine equation

$x^2 - a\left( {\frac{{b^k - 1}} {{b - 1}}} \right)^2 = 1$

has at most three solutions in positive integers. Moreover, they showed that if max{a, b } > 4.76 · 1051, then there are at most two positive integer solutions (x, k). In this paper, we sharpen their result by proving that this equation always has at most two solutions.

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Correspondence to Alain Togbé.

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Cipu, M., Mignotte, M. & Togbé, A. On the size of the intersection of two Lucas sequences of distinct type II. Sci. China Math. 54, 1299–1316 (2011). https://doi.org/10.1007/s11425-011-4242-5

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  • DOI: https://doi.org/10.1007/s11425-011-4242-5

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