Now we've also said that if we had, if we had n things that we want to permute into n places, well this really should just be n factorial. The first place has, you know, let's just do this. So this is the first place, this is the second place, this is the third place, all the way you get to the nth place. Well, there would be n possibilities for who's in the first position or which object is in the first position. And then for each of those possibilities, there would be n minus one possibilities for which object you choose to put in the second position because you've already put one into that position. Now for each of these n times n minus one possibilities where you've placed two things, there would be n minus two possibilities of what goes in the third position and then you would just go all the way down to one. And this thing right over here is exactly what we wrote over here.