And you'll get the probability that no one shares the same birthday with anyone else. But before we do that, let me just show you something that might make it a little bit easier. Is there any way that I can mathematically express this with factorials, or that I could mathematically express this with factorials? Well, let's think about it. 365 factorial is what? 365 factorial is equal to 365 times 364 times 363 times all the way down to 1, right? You just keep multiplying, it's a huge number.