Answer:
8*2^(n-1)
Explanation:
This is a geometric sequence since we multiply from the previous term.
a_n = a_1 * common ratio^(n-1) where a_n is the nth number and a_1 is the first.
The first term is 8, so we have
a_n = 8*<common ratio>^(n-1) = 8*2^(n-1)