Factorial in OCaml

Example for versions OCaml 3.11

This example shows the naive way to implement the factorial function. However, it is not tail recursive, since the recursive function call is not the only statement on the line. 

let rec factorial n =
    if n <= 1 then
      1
    else
      factorial (n-1) * n;;

let () =
  for n = 0 to 16 do
    Printf.printf "%d! = %d\n" n (factorial n)
  done;