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FACTDOUBLE
This function calculates the double factorial of the specified number.
Syntax
FACTDOUBLE(number)
Arguments
[Required] The value for which to return the double factorial. If number is not an integer, it is truncated.
Remarks
The number argument must be a non-negative number. If you provide a number that is not an integer for the number argument, the decimal portion of the number is ignored.
The double factorial is calculated as follows for even numbers:
n!! = n(n-2)(n-4) ... (4)(2)
The double factorial is calculated as follows for odd numbers:
n!! = n(n-2)(n-4) ... (3)(1)
Examples
FACTDOUBLE(E3)
FACTDOUBLE(R3C5)
FACTDOUBLE(6) gives the result 48