FACT

Calculates the factorial[1] of a number.

Syntax:

FACT(n:number)

Returns the factorial of n (most commonly shortened to n!).

n must be an integer greater than or equal to zero.

Formula:

n! = i=n i

i.e.

n! = n × (n − 1) ... × 2 × 1

  1. Weisstein, Eric W. "Factorial." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/Factorial.html