A = n * n;
B = n * n + n + 1;
C = n * n + 1;
A ^ 2 + B ^ 2
n^4 + (n ^ 2 + n + 1) * (n ^ 2 + n + 1)
n^4 + n ^ 4 + 2 * n^3 + 3*n^2 + 2*n + 1
2*n^4 + 2*n^3 + 2*n^2 + 2 * n + n^2 + 1
2 * n*(n ^ 3 + n ^ 2 + n + 1) + n^2 + 1
2 * n ( n(n ^ 2 + 1) + (n ^ 2 + 1)) + n^2 + 1
2 * n((n^2 + 1)(n + 1)) + (n ^ 2 + 1)
(n ^ 2 + 1)(2 * n * (n + 1) + 1)