Songklanakarin Journal of Science and Technology (SJST) (Jun 2022)

The Fermat-type equation with signature (2, 2, n) and Bunyakovsky conjecture

  • Sawian Jaidee,
  • Korakot Saosoong

DOI
https://doi.org/10.14456/sjst-psu.2022.104
Journal volume & issue
Vol. 44, no. 3
pp. 779 – 784

Abstract

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We first discuss the Fermat-type equation with signature (2, π‘š, 𝑛), which is the Diophantine equation in the shape π‘₯ 2 + 𝑦 π‘š = 𝑧 𝑛 , where π‘₯, 𝑦 and 𝑧 are unknown integers, and π‘š, 𝑛 are fixed positive integers greater than 1. This kind of equations has been particularly focused on our work here in the case π‘š = 2, 𝑛 = 5 and 𝑦 = 𝑝 is a fixed rational prime. Then the first result describing the condition of such a prime 𝑝 in order to illustrate that this certain equation has an integer solution (π‘₯, 𝑦) when 𝑝 ≑ 1(mod 4) and gcd(π‘₯, 𝑝) = 1, and the second result stating that the equation has no integer solution (π‘₯, 𝑦) when 𝑝 ≑ 3(mod 4) are provided. Lastly, we will indicate that the results of Be ́rczes and Pink about solving the equation π‘₯ 2 + 𝑝 2π‘˜ = 𝑧 𝑛 in 2008 have been generalized in the particular cases (𝑛, π‘˜) = (3,1) and (5,1), and additionally present that the first result and also its analogous result in the particular case 𝑛 = 3 can be linked to the Bunyakovsky conjecture.

Keywords