Recursion depth = 0 local1 = 0, local2 = 0

  Recursion depth = 1 local1 = 3, local2 = 7

    Recursion depth = 2 local1 = 6, local2 = 14

      Recursion depth = 3 local1 = 9, local2 = 21

        Recursion depth = 4 local1 = 12, local2 = 28

          Recursion depth = 5 local1 = 15, local2 = 35

            Recursion depth = 6 local1 = 18, local2 = 42

              Recursion depth = 7 local1 = 21, local2 = 49

                Recursion depth = 8 local1 = 24, local2 = 56

                  *** Base Case depth = 9

                Return from depth = 8 local1 = 24, local2 = 56

              Return from depth = 7 local1 = 21, local2 = 49

            Return from depth = 6 local1 = 18, local2 = 42

          Return from depth = 5 local1 = 15, local2 = 35

        Return from depth = 4 local1 = 12, local2 = 28

      Return from depth = 3 local1 = 9, local2 = 21

    Return from depth = 2 local1 = 6, local2 = 14

  Return from depth = 1 local1 = 3, local2 = 7

Return from depth = 0 local1 = 0, local2 = 0