geometric sequence:
1st 2nd 3rd 4th
3, 6, 12, 24,...
an = 2 * 3n - 1
an = 3 * 2n - 1
an = 2 + 3(n-1)
an = 3 + 2(n-1)
n = term number
first term = 3 ; common ratio is 2
a(n) = 3 * 2(n-1)
a(3) = 3 * 2(3-1)
a(3) = 3 * 2(2)
a(3) = 3 * 4
a(3) = 12 correct.
a(n) = 3 * 2(n-1)
