Question

What is the fourth term of the sequence a1=m an= 2an-1

Answer 1

8m

Explanation:

We assume you're describing a geometric sequence with first term m and common ratio 2. Then the n-th term is ...

a[n] = m·2^(n-1)

and the fourth term is

a[4] = m·2^(4-1) = 8m