MathDB
y^2 + xy + 3x = n(x^2 + xy + 3y)

Source: JBMO 2011 Shortlist N3

October 14, 2017
JBMOnumber theory

Problem Statement

Find all positive integers nn such that the equation y2+xy+3x=n(x2+xy+3y)y^2 + xy + 3x = n(x^2 + xy + 3y) has at least a solution (x,y)(x, y) in positive integers.