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.
((V^Y) sum ((W^n)(Y-1+n)!/((Y-1)!n!)) from n=0 to (X-1)) = 1-e^(-M) sum ((M^m)/(m!) from m=0 to (Y-1))
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random