User blog:Commando Conceptor L5 5.12.159.141/Tetrational factorial

The tetrational factorial is a function by Commando Conceptor L5 5.12.159.141.It is equal to and represented by n!!2.It is a tetrational version of the factorial.

Examples

 * 0!!2=1
 * 5!!2=
 * 10!!2=