LISP function to solve Ackermann’s function

2 - Define a LISP function to solve Ackermann’s function

   Implementation Code in LISP -

     (defun ackermann(m n) “The Ackermann Function”

     (cond ((= m 0)(+ n 1))

      ((= m 1)(+ n 2))

      ((= m 2)(+  3(* n 2)))

      ((= m 3)(+ 5 (* 8(- (expt 2 n) 1))))

      (t (cond ((= n 0) (Ackermann (- m 1) 1))

      (t (Ackermann (- m 1) (Ackermann m (- n 1))))

      ))))

    OUTPUT-

    (Ackermann 2 3)

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