To calculate the negative integer factorial function, you can use the formula n! = (-1)^n * |n|!, where n is the negative integer. For example, to find (-5)!, you would use the formula (-5)! = (-1)^-5 * |(-5)|! = -1 * 5! = -120.
No, the negative integer factorial function is only defined for negative integers. It cannot be extended to non-integer values.
By convention, 0! is equal to 1. (-1)! is undefined as it is not a negative integer.
The negative integer factorial function has similar properties to the positive integer factorial function. For example, (-n)! = (-1)^n * n! and (-n)! = (-n+1)! / (-n) for all negative integers n.
The negative integer factorial function has many applications in mathematics, such as in the study of combinatorics and probability. It is also used in the development of advanced mathematical concepts, such as the gamma function.