(defun mod-inverse (a m)
  (let ((m0 m) (y 0) (x 1))
    (if (= m 1)
        0
        (progn
          (loop while (> a 1) do
               (let ((q (floor a m))
                     (temp m))
                 (setf m (mod a m)
                       a temp)
                 (setf temp y
                       y (- x (* q y))
                       x temp)))
          (if (< x 0)
              (+ x m0)
              x)))))

(defun comb-lut (N MOD)
  (let ((F (make-array (1+ N) :initial-element 1))
        (InvF (make-array (1+ N) :initial-element 1)))
    (loop for i from 1 to N do
         (setf (aref F i) (mod (* (aref F (1- i)) i) MOD)))
    (setf (aref InvF N) (mod-inverse (aref F N) MOD))
    (loop for i from (1- N) downto 0 do
         (setf (aref InvF i) (mod (* (aref InvF (1+ i)) (1+ i)) MOD)))
    (lambda (n r)
      (assert (and (<= 0 n N) (<= 0 r)))
      (if (<= 0 r n)
          (mod (* (mod (* (aref F n) (aref InvF r)) MOD)
                  (aref InvF (- n r)))
               MOD)
          0))))

(defun main ()
  (let* ((MOD 998244353)
         (N (read))
         (A (loop for i from 1 to N collect (read)))
         (comb (comb-lut (+ N (apply #'max A)) MOD))
         (ans 1))
    (loop for q from 1 to N
          for a in A do
          (setf ans (mod (+ ans (funcall comb (+ q a -1) q)) MOD)))
    (princ ans)(terpri)))

(main)