Pardon my English as I'm not a native speaker of the language and I'm not a big math guy, so please bear with me and my ignorance for a bit. I've unconsciously stumbled upon something that's most probably blatantly obvious and easy, yet I have no idea how to explain it. So here it goes:
$$11! = 39916800$$ $$10! = 3628800$$ $$11! - 10! = 39916800 - 3628800 = 36288000$$
As you can see, the result equals the value that $10!$ returns "plus" an extra digit added. Is this just a cool coincidence or is there any logic behind that I'm just not aware of?