This problem has been bugging me for a while. There is no common ratio and I don't know if its telescopable. Help and thank you!

\(\sum_{n=1}^{\infty} \frac{n^3}{3^n}\)

DragonLord Mar 24, 2020

#1**+1 **

Hey, DragonLord...if you send this one to heureka he might know how to fnd the result mathematically...he's pretty good with this kind of thing.....

CPhill Mar 24, 2020

#3**0 **

I tried rewriting the bases as powers of three.

Then, I tried diving by three and multiplying the series by three

but it did not work.

27/27 looks very fishy, might be the key to the problem.

tertre Mar 25, 2020

#5**+1 **

I understand guest, but an answer to me is completely meaningless if there is no process or explanation on the way there.

DragonLord Mar 25, 2020