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.
0.5 + sum_1^n (0.5 + 0.5 × 2^k) = 99999
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random