in mechanic'calculator(windows xp) show: 3.6!=13.381285870 how? what's meaning of 3.6!?

Question

we know n!=n(n-1)(n-2).....1 and n belong natural number

Answer 1

There's a continuous version of the factorial function called the "gamma function".

Details at:

http://en.wikipedia.org/wiki/Gamma_function

Answer 2

Jims is sorta right. I wouldn't call the gamma function a continuous version of the factorial. I would say that the factorial is related to the gamma function on the postive integers!

Since 3! is 6 and 4! is 24 then at least 3.6! is in the proper range.