Calculation method:
Greater than or equal to 1
The factorial representation of any natural number with n greater than or equal to 1: or
Factorial of 0 0! = 1。
Extended data:
Definition scope of factorial:
Usually, the factorial we are talking about is defined in the range of natural numbers (most scientific calculators can only calculate the factorial of 0 ~ 69), and decimal scientific calculators have no factorial function, such as 0.5! ,0.65! ,0.777! It's all wrong
But sometimes we define the Gamma function as the factorial of non-integers, because when x is a positive integer n, the value of the Gamma function is the factorial of n- 1
Gamma function (gamma function)
Define gamma function:?
Using the knowledge of integral, we can prove that γ (s) = (s) × γ (s- 1).
So, when x is an integer n,? In this way, the gamma function is actually a continuation of factorial.
References:
Baidu encyclopedia-factorial