Determine-all-functions-f-N-N-satisfying-xf-y-yf-x-x-y-f-x-2-y-2-for-all-positive-integers-x-and-y-

Question Number 55358 by gunawan last updated on 22/Feb/19

Determine all functions f : N \to N

satisfying

x f (y) + y f (x) = (x + y) f (x^{2} + y^{2})

for all positive integers x and y