Returns the double factorial of the given number.
Sample Usage
FACTDOUBLE(5)
FACTDOUBLE(C5)
Syntax
FACTDOUBLE(number)
- number - The number for which the double factorial is to be computed.
Examples
FACTDOUBLE(5) returns the number 15.
FACTDOUBLE(C5) returns the double factorial of the number contained in C5.
Notes
- Decimal inputs will be truncated.
- If is number is odd, double factorial is calculated as follows:
- n!! = n*(n-2)*(n-4)...(3)(1)
- If is number is even, double factorial is calculated as follows:
- n!! = n*(n-2)*(n-4)...(4)(2)