1 x 25 x 6 x 7 9 2 5 3x 15 July 8, 2019 16 32 64 128 5 x 7 = 35 (25 ^ x - 5 ^ (x + 2) + 26)/(5 ^ x - 1) + (25 ^ x - 7 * 5 ^ x + 1)/(5 ^ x - 7) = 2 * 5 ^ x - 24 1 25 x 7
