n!
i1 : 30! o1 = 265252859812191058636308480000000
i2 : 30.! o2 = 2.65252859812191e32 o2 : RR (of precision 53)
i3 : 30.01! o3 = 2.74475749473282e32 o3 : RR (of precision 53)
The object ! is a keyword.
This operator may be used as a postfix unary operator in an expression like x!. The user may install a method for handling such expressions with code such as
X ! := (x) -> ...
where X is the class of x.