factorial

Part of the TechTarget Network of Enterprise IT Web Sites
Home Look It Up ITKnowledge Exchange Fast References Products White Papers Blogs

Search our IT-specific encyclopedia for:
 
OR Jump to a topic:
 
Advanced Search
Browse alphabetically:
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 #
All Categories Computing Fundamentals

factorial

The factorial, symbolized by an exclamation mark (!), is a quantity defined for all integer s greater than or equal to 0.

For an integer n greater than or equal to 1, the factorial is the product of all integers less than or equal to n but greater than or equal to 1. The factorial value of 0 is defined as equal to 1. The factorial values for negative integers are not defined.

Mathematically, the formula for the factorial is as follows. If n is an integer greater than or equal to 1, then

n ! = n ( n - 1)( n - 2)( n - 3) ... (3)(2)(1)

If p = 0, then p ! = 1 by convention.

The factorial is of interest to number theorists. It often arises in probability calculations, particularly those involving combinations and permutations. The factorial also arises occasionally in calculus and physics.

Compare double factorial .













Read more about it at:
> Eric Weisstein's Mathworld defines and discusses the factorial.
Last updated on: Sep 21, 2005

Are you a Know-IT-All?
What operating system will soon have comedian Jerry Seinfeld as its spokesman?
Answer

WORD OF THE DAY...
softcooling
LEARN MORE ABOUT...
Managing SharePoint services
Buzzword Alert: Mechanical Turk
Our Favorite Cheat Sheets
Our Latest Discovery
57 technology-specific sites
WhatIs.com RSS Feeds
Home Look It Up ITKnowledge Exchange Fast References Products White Papers Blogs
About Us   |   Contact Us   |   For Advertisers   |   For Business Partners   |   Reprints   |   RSS   |   Awards
TechTarget provides enterprise IT professionals with the information they need to perform their jobs - from developing strategy, to making cost-effective IT purchase decisions and managing their organizations' IT projects - with its network of technology-specific Web sites, events and magazines.

TechTarget Corporate Web Site  |  Media Kits  |  Reprints  |  Site Map




All Rights Reserved, Copyright 2008, TechTarget | Read our Privacy Policy
  TechTarget - The IT Media ROI Experts