# Math Help - find a summation for a given series

1. ## find a summation for a given series

1+a(a+1)+a(a+1)(a-2)(a+3)+a(a+1)(a-2)(a+3)(a-4)+a(a+1)(a-2)(a+3)(a-4)(a+5)

what can be a general summation could be written in the form $\sum_{n = 0}^{\infty}a_n$

2. a = first number in sequence
r = ratio

Hope that helps.

3. Originally Posted by mrbuttersworth
a = first number in sequence
r = ratio

Hope that helps.
How did you get that result? This is not a geometric series.

-Dan

4. oh wow, I apologize, I read that one too quickly. Well in that case, I'm stumped. Sorry about that first response. That's a general solution for the sum of a geometric series.