Nothing
P_mass <-
function(N,m,n,x) exp(lchoose(N,x)+lchoose(N-x,m-x)+lchoose(N-m,n-x)
-lchoose(N,m)-lchoose(N,n))
Any scripts or data that you put into this service are public.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.