# FACTDOUBLE

Spread for WinForms provides advanced software components that support Excel import/export, full cell customization, an extensive calculation engine with over 450 functions and more, all with zero dependencies on Excel.

## Content



This function calculates the double factorial of the specified number.

## Syntax

FACTDOUBLE(*number*)

## Arguments

The argument can be any non-negative numeric value.

## 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)

## Data Types

Accepts numeric data. Returns numeric data.

## Examples

`FACTDOUBLE(E3)`
`FACTDOUBLE(R3C5)`
`FACTDOUBLE(6)` gives the result 48

## Version Available

This function is available in product version 1.0 or later.

## See Also

[FACT](/spreadnet/docs/latest/online-formula/formulas-functionsall/formulas-functsDtoG/FunctionFACT) \| [PRODUCT](/spreadnet/docs/latest/online-formula/formulas-functionsall/formulas-functsMtoQ/FunctionPRODUCT) \| [Math and Trigonometry Functions](/spreadnet/docs/latest/online-formula/formulas-overview/formulas-functs/formulas-functtypes/formulas-functsmathtrig)