Find the next number in the series ?

Question

1 + 1 = 8
2 + 2 = 32
3 + 3 = 72
4 + 4 = ? …

Answer 1

its 128.

Answer 2

Ans : 128

result = ( number * number) * 8

8 * (1 * 1) = 8
8 * (2 * 2) = 32
8 * (3 * 3) = 72
8 * (4 * 4) = 128