Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
\sum_{n=0}^{infinity} \frac{6*5^n-15*4^n+20*3^n-15*2^n+6}{6^n}
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random