(defun factorial (n)
  (if (< n 2) 1 (* n (factorial (1- n)))) )

(defun primep (n)
 "Primality test using Wilson's Theorem"
  (unless (zerop n)
    (zerop (mod (1+ (factorial (1- n))) n)) ))

(defun ispal (n)
  "Is integer n a palindrome?"
  (setq a (write-to-string n))
  (return-from ispal (string-equal a (reverse a)))
  )

(defun char-to-int (char) (- (char-int char) (char-int #\0))) ; convert single char 0-9 to integer 

(defun sum-digits (list1)
       (setq sum1 0)
       (loop for item in list1 do (setq sum1 (+ (char-to-int item) sum1)))
       (return-from sum-digits sum1)
       )


(defun prime-sumdig-pal  ()
       (loop for cand from 10000 to 11000 do  (progn
             (if (primep cand) (progn
                 (setq l1 (write-to-string cand))
                 (setq list1 (coerce l1 'list))
                 (setq sum1 (sum-digits list1))
                 (if (ispal sum1) (print (list cand sum1)))
                 )
             )
          )
       )
)