most recent 30 from http://mathoverflow.net 2013-05-20T13:27:55Z http://mathoverflow.net/feeds/user/20441 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/10124/the-factorial-of-1-2-3/85197#85197 John O 2012-01-08T15:37:52Z 2012-01-08T23:00:35Z

<p>As 0! and 1! = 1 ,<br> 2! = 2,<br> 3! = 6 and so on</p> <p>Can we not have</p> <p>-1! = -1<br> -2! = 2 = -1 X -2<br> -3! = -6 = -1 X -2 X -3<br> -4! = 24 = -1 X -2 X -3 X -4<br> -5! = -120 = -1 X -2 X -3 X -4 X -5 </p> <p>...and so on?</p> <p>It would produce some sort of series but would they be of any use anywhere?</p>