Ramanujan's formulas of pi in Common Lisp

pi.lisp

(defun fact (n)
  (let ((r 1))
    (loop
       for i from 2 to n
       do (setf r (* i r))
       finally (return r))))

(defun calc-pi-1 (max)
  (/ 1
     (* (/ (* 2 (sqrt 2.0d0)) (expt 99 2))
	(loop
	   for n from 0 to max
	   sum (/ (* (fact (* 4 n)) (+ 1103 (* 26390 n)))
		  (expt (* (expt 4 n) (expt 99 n) (fact n)) 4))))))

(defun calc-pi-2 (max)
  (/ 4
     (loop
	for n from 0 to max
	sum (/ (* (expt -1 n) (fact (* 4 n)) (+ 1123 (* 21460 n)))
	       (* (expt 882 (+ (* 2 n) 1)) (expt (* (expt 4 n) (fact n)) 4))))))