Inverse Factorial

After I had a conversation with a friend on a very long bus ride about inverse factorial a stork came and put this page on the web.
 My Pages: Before we look at inverse factorial lets look at factorial: ~The most commonly used definition of factorial is only defined for non negative integers. This definition of factorial is: n!= n*(n-1)*(n-2)*(n-3)…3*2*1 Note:    0!=1 ~However as the above definition is not defined for non integers or negative values I will use: n!= Gamma(n-1) where gamma is defined as:    Or in words: the area under the curve of  with values of t ranging from 0 to infinity.~For more on the gamma function go to: ~Looking at Inverse factorial: ~Inverse factorial is just the inverse function of factorial~I would use Γ-1 (n) to define the inverse gamma function     however I have seen n? usedt to mean inverse factorial (this comes from Halfbakery) ~Now Lets look at what the factorial function looks like:   ~ x {0,3} ~ x {0,10} ~And my personal favoritex: {0,100} ~And here are the graphs of Inverse Factorial:   ~ y {0, 3} ~ y {0, 10} ~ y {0, 150} ~A note: be careful inverse factorial is not a function so there are multiple values for any one x (unless you limit the domain to x>/=1)