Costa Rican math olympiad 2008 Problem 5
Source:
June 18, 2009
Diophantine equationOther problems
Problem Statement
Let be a prime number such that p\minus{}1 is a perfect square. Prove that the equation
a^{2}\plus{}(p\minus{}1)b^{2}\equal{}pc^{2}
has infinite many integer solutions , and with (a,b,c)\equal{}1