(* sum the numbers from 0 to n sumTo 0 = 0 sumTo 3 = 6 sumTo (-1) = 0 *) let rec sumTo (n:int) : int = if n <= 0 then 0 else n + sumTo (n-1) let _ = Printf.printf "The sum of the numbers from 0 to 8 is %d\n" (sumTo 8)