1. factorial - Noun
2. factorial - Adjective
Of or pertaining to a factory.
Related to factorials.
A name given to the factors of a continued product when the former are derivable from one and the same function F(x) by successively imparting a constant increment or decrement h to the independent variable. Thus the product F(x).F(x + h).F(x + 2h) . . . F[x + (n-1)h] is called a factorial term, and its several factors take the name of factorials.
The product of the consecutive numbers from unity up to any given number.
Source: Webster's dictionary1, 2, 6, 24, and 120 are factorials Source: Internet
Although Euler was a pioneer in the theory of complex variables, he does not appear to have considered the factorial of a complex number, as instead Gauss first did. Source: Internet
A more restrictive property than satisfying the above interpolation is to satisfy the recurrence relation defining a translated version of the factorial function, : for x equal to any positive real number. Source: Internet
An obvious way to generate permutations of n is to generate values for the Lehmer code (possibly using the factorial number system representation of integers up to n!), and convert those into the corresponding permutations. Source: Internet
Even for ordinary permutations it is significantly more efficient than generating values for the Lehmer code in lexicographic order (possibly using the factorial number system ) and converting those to permutations. Source: Internet
A passcode of four digits, if the four digits in question are known, is reduced from 10,000 possibilities to just 24 possibilities (10 4 versus 4! ( factorial of 4)). Source: Internet