let 0 =
  fun f -> fun init ->
    init
in

let +1 =
  fun n ->
    fun f -> fun init ->
      f (n f init)
in

let 1 = +1 0 in
let 2 = +1 1 in
let 3 = +1 2 in
let 4 = +1 3 in
let 5 = +1 4 in

let print_n =
  fun n ->
    n (fun accumulator -> print foo accumulator) (fun x -> x)
in

let + =
  fun n -> fun n' -> n +1 n'
in

let * =
  fun n -> fun n' -> n (n' +1) 0
in

print_n (* 4 3)