Syntax for a series summation (Sigma)

[upshaw211]

Thanks for the tip. I was hoping there would be more efficient way o
doing it, but this way works just fine. Thanks

 

[Myrna Larson]

There is. I gave you an array formula in response to your duplicate post in
the worksheet functions group.

Please don't post the same questions to multiple groups. If I had known you
were satisfied with a solution that requires additional cells, I wouldn't
have wasted a half-hour or more developing and testing the array formula