On the complete solutions of a generalized Lebesgue-Ramanujan-Nagell equation

Abstract

We consider the generalized Lebesgue-Ramanujan-Nagell equation $x^2+17^{k}41^{\ell }59^m=2^{\delta }{y}^n$ in the unknown integers $x\ge 1,y>1,n\ge 3$ and $k,\ell ,m\ge 0$ satisfying $\gcd (x,y)=1$. We first find all the integer solutions of the above equation, and then use this result to determine all the integer solutions of some other Lebesgue-Ramanujan-Nagell type equations. Our method uses the classical results of Bilu, Hanrot and Voutier on existence of primitive divisors of Lehmer sequences in combination with number theoretic arguments and computer search.

arXiv comment15 pages. Incorporated some comments/suggestions made by referees. To appear in `Quaestiones Mathematicae'