RosettaCodeData/Task/Factorial/00DESCRIPTION

;Definitions:
:* &nbsp; The factorial of &nbsp; '''0''' &nbsp; (zero) &nbsp; is [[wp:Factorial#Definition|defined]] as being &nbsp; 1 &nbsp; (unity).
:* &nbsp; The &nbsp; '''Factorial Function''' &nbsp; of a positive integer, &nbsp; <big> ''n'', </big> &nbsp; is defined as the product of the sequence:
                 <big><big> ''n'', &nbsp; ''n''-1, &nbsp; ''n''-2, &nbsp; ... &nbsp; 1 </big></big>


;Task:
Write a function to return the factorial of a number.

Solutions can be iterative or recursive.

Support for trapping negative &nbsp; <big> ''n'' </big> &nbsp; errors is optional.


;Related task:
* &nbsp; [[Primorial numbers]]
<br><br>
2016 Update 2016-12-05 22:15:40 +01:00			`;Definitions:`
September 2017 Update 2017-09-23 10:01:46 +02:00			`:*   The factorial of   '''0'''   (zero)   is [[wp:Factorial#Definition\|defined]] as being   1   (unity).`
2016 Update 2016-12-05 22:15:40 +01:00			`:*   The   '''Factorial Function'''   of a positive integer,   <big> ''n'', </big>   is defined as the product of the sequence:`
			`<big><big> ''n'',   ''n''-1,   ''n''-2,   ...   1 </big></big>`
A-M baby 2013-04-10 21:29:02 -07:00
2016 Update 2016-12-05 22:15:40 +01:00
			`;Task:`
Just another update 2015-02-20 00:35:01 -05:00			`Write a function to return the factorial of a number.`
2016 Update 2016-12-05 22:15:40 +01:00
Just another update 2015-02-20 00:35:01 -05:00			`Solutions can be iterative or recursive.`
2016 Update 2016-12-05 22:15:40 +01:00
			`Support for trapping negative   <big> ''n'' </big>   errors is optional.`
June 2018 Update 2018-06-22 20:57:24 +00:00

			`;Related task:`
			`*   [[Primorial numbers]]`
2016 Update 2016-12-05 22:15:40 +01:00			`<br><br>`