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arXiv · 2111.05626

A modular approach to the generalized Ramanujan-Nagell equation

Elif Kızıldere Mutlu·Maohua Le·Gökhan Soydan
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Abstract

Let $k$ be a positive integer. In this paper, using the modular approach, we prove that if $k\equiv 0 \pmod{4}$, $30< k<724$ and $2k-1$ is an odd prime power, then under the GRH, the equation $x^2+(2k-1)^y=k^z$ has only one positive integer solution $(x,y,z)=(k-1,1,2)$. The above results solve some difficult cases of Terai's conecture concerning this equation.

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Elif Kızıldere Mutlu, Maohua Le, Gökhan Soydan. 2021-11-10. A modular approach to the generalized Ramanujan-Nagell equation. https://arxiv.org/abs/2111.05626

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