How to use FACTDOUBLE function in Excel?
The FACTDOUBLE function in Excel is used to calculate the double factorial of a nonnegative integer The double factorial of a number n denoted as n is the product of all the integers from 1 up to n that have the same parity odd or even as n For example if n is even the double factorial would be n n2 n4 2 if n is odd it would be n n2 n4 1