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.
(40 choose 9) - ((40/2 - 1)*40/2)*(37 choose 6)/(9 choose 3)
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random