Question

what is the Recursive Formula and the Explicit Formula for Let a1=2, 9, 16, 23, and Let a1=2, 14, 98, 686, ...

Answer 1

Explanation:

I don’t know why they bother teaching recursive formulas as the explicit is almost always used :)

For 2,9,16,23...

Recursive is a(n+1)=an+7

Explicit is an=2+7(n-1)

(or more neatly an=7n-5)

For 2,14,98,686...

Recursive is a(n+1)=7an

Explicit is an=2(7^(n-1))

(or (2/7)7^n )