fun fib x =
    if x = 0 then
       0
    else if x = 1 then
       1
    else
       fib (x-2) + fib (x-1)

fun loop i =
    if i > 20 then
       ()
    else
       (
       print ("Fib(" ^ Int.toString i ^ ") = ");
       print (Int.toString (fib i));
       print "\n";
       loop (i+1)
       )

val () = loop 0