Abstract
A Pell Fermat equation and its two classes of solutions are discussed. We give a formula for the pairs of positive solutions, written with the Pell numbers, and some new identities involving these numbers. We build an invariant modulo 4 for each class of solutions.

Keywords
Pell numbers, Pell-Lucas numbers, Markoff equation

Cite this paper
Serge PERRINE, About the diophantine equation z²= 32y² – 16 , SCIREA Journal of Mathematics. Volume 4, Issue 5, October 2019 | PP. 126-139.

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