Definition:Factorial

Definition
Let $n \in \Z_{\ge 0}$ be a positive integer.

Also known as
While the canonical vocalisation of $n!$ is $n$ factorial, it can often be found referred to as $n$ bang or (usually by schoolchildren) $n$ shriek.

Some mathematicians prefer $n$ gosh.

Some early sources favour factorial $n$

Also see

 * Definition:Gamma Function: the extension to the complex plane


 * Definition:Rising Factorial
 * Definition:Falling Factorial


 * Equivalence of Definitions of Factorial