Answer:
an = 4^(n-1)
Step-by-step explanation:
The three given terms have a common ratio of 4:
4/1 = 16/4 = 4
So, this can be described by the function for a geometric sequence:
an = a1×r^(n -1)
where an is the n-th term, a1 is the first term (1) and r is the common ratio (4).
an = 1×4^(n-1)
an = 4^(n -1) . . . . . simplified
