Let m$m$ and n$n$ be positive integers less than 2000$2000$ which satisfies the equation(m^2-mn-n^2)^2=1 $(m^2-mn-n^2)^2=1$. How can we determine the largest possible value of the expression m^2+n^2.$m^2+n^2$?
Post Closed as "Not suitable for this site" by abx, Felipe Voloch, Emil Jeřábek, Max Alekseyev, Daniele Tampieri