MathDB
equation 4

Source:

November 8, 2010
number theorynumber theory unsolved

Problem Statement

Solve in equation: x2+y2+z2+w2=3(x+y+z+w) x^2+y^2+z^2+w^2=3(x+y+z+w) where x,y,z,w x,y,z,w are positive integers.