Memoized lisp code can be better about fib HOT 2 CLOSED

(defun fib (n)
  (labels ((fib* (xno x-2 x-1)
             (if (= xno n)
                 (+ x-2 x-1)
                 (fib* (1+ xno) x-1 (+ x-1 x-2)))))
    (if (<= n 1)
        n
        (fib* 2 0 1))))

(defun fib-memoized (n)
  (let ((memo (make-array (1+ n) :initial-element nil)))
    (labels ((memofib (n)
               (or (aref memo n)
                   (setf (aref memo n)
                         (if (<= n 1)
                             n
                             (+ (memofib (- n 1))
                                (memofib (- n 2))))))))
      (memofib n))))