Question

If mc005-1.jpg, what are the first three terms of the sequence defined by the recursive formula below?

mc005-2.jpg
8, 26, 80
2, 8, 26
8, 2, 0
5, 8, 26

Answer 1

Use the recursion a_{n+1} = 3a_n + 2 with a_1 = 2.

a_2 = 3(2) + 2 = 8
a_3 = 3(8) + 2 = 26

So the first three terms are 2, 8, 26.