On the Diophantine equation $cx^2+p^{2m}=4y^n$

Kalyan Chakraborty; Azizul Hoque; Kotyada Srinivas

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arXiv · 2102.07977

On the Diophantine equation $cx^2+p^{2m}=4y^n$

Kalyan Chakraborty·Azizul Hoque·Kotyada Srinivas

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Abstract

Let $c$ be a square-free positive integer and $p$ a prime satisfying $p\nmid c$. Let $h(-c)$ denote the class number of the imaginary quadratic field $\mathbb{Q}(\sqrt{-c})$. In this paper, we consider the Diophantine equation $$cx^2+p^{2m}=4y^n,~~x,y\geq 1, m\geq 0, n\geq 3, \gcd(x,y)=1, \gcd(n,2h(-c))=1,$$ and we describe all its integer solutions. Our main tool here is the prominent result of Bilu, Hanrot and Voutier on existence of primitive divisors in Lehmer sequences.

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Kalyan Chakraborty, Azizul Hoque, Kotyada Srinivas. 2021-02-16. On the Diophantine equation $cx^2+p^{2m}=4y^n$. https://arxiv.org/abs/2102.07977

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