n + 1 63 --------------- 2*n + 1 n - 2 3 *7
-1 - 2*n 2 - n 1 + n 3 *7 *63
3.0^(-1.0 - 2.0*n)*7.0^(2.0 - n)*63.0^(1.0 + n)
1029
-1 - 2*n 2 - n n + 1 3 *7 *63
-2*n -n n 1029*3 *7 *63