General term of a series

1. Sep 21, 2014

smart_worker

1. The problem statement, all variables and given/known data

Find the general term and test the nature of the series:

2. Relevant equations

1+1*4+1*4*7+...

3. The attempt at a solution

Term N = Term (N-1) * 3N-2

Hence,3(N-1)-2 * 3N-2

which simplifies to (3N-5)(3N-1) = 9N^2 - 18N + 5

Is this correct?

2. Sep 21, 2014

LCKurtz

No. Each term of your series has one more factor in it. So the nth term would have to written like$$a_n = 1\cdot 4 \cdot 7 ...(\text{something involving }n)$$where that "something" is a formula for the last factor of $a_n$.