Difference between revisions of "Factorial"
From specialfunctionswiki
| Line 1: | Line 1: | ||
Let $n$ be an integer. Then the factorial of $n$, written $n!$, is the integer | Let $n$ be an integer. Then the factorial of $n$, written $n!$, is the integer | ||
| − | $$n!=n(n-1)(n-2)\ldots 3 \cdot 2 \cdot 1.$$ | + | $$n!=\displaystyle\prod_{k=1}^n k=n(n-1)(n-2)\ldots 3 \cdot 2 \cdot 1.$$ |
The most common way to interpolate this function to allow complex inputs is via the [[gamma function]]. | The most common way to interpolate this function to allow complex inputs is via the [[gamma function]]. | ||
Revision as of 22:37, 28 April 2016
Let $n$ be an integer. Then the factorial of $n$, written $n!$, is the integer $$n!=\displaystyle\prod_{k=1}^n k=n(n-1)(n-2)\ldots 3 \cdot 2 \cdot 1.$$ The most common way to interpolate this function to allow complex inputs is via the gamma function.
