powered by Google (TM)
index: click on a letter
A B C D E
F G H  I  J
K L M N O
P Q R S T
U V W X Y
Z A to Z index
index: subject areas
numbers & symbols
sets, logic, proofs
geometry
algebra
trigonometry
advanced algebra
& pre-calculus
calculus
advanced topics
probability &
statistics
real world
applications
multimedia
entries
about mathwords  
website feedback  


Factorial

The product of a given integer and all smaller positive integers. The factorial of n is written n! and is read aloud "n factorial".

Note: By definition, 0! = 1.

 

Formula: n! = n·(n – 1)·(n – 2) · · · 3·2·1
Example: 6! = 6·5·4·3·2·1 = 720

 

See also

Permutation formula, combination formula, binomial coefficient

 


  this page updated 27-aug-12
Mathwords: Terms and Formulas from Algebra I to Calculus
written, illustrated, and webmastered by Bruce Simmons
NCTM Web Bytes December 2004 Web Bytes March 2005 Web Bytes