In the course of the following proofs, we will use a very simple case of Euler’s trick: If x, y are integers of the same parity, then there exist integers z, w such that x2 + y2 = 2(z2 + w2). This is because of the following identity
In the course of the following proofs, we will use a very simple case of Euler’strick: If x, y are integers of the same parity, then there exist integers z, w suchthat x2 + y2 = 2(z2 + w2). This is because of the following identity