# Problem 294: Sum of digits - experience #23
For a positive integer k, define d(k) as the sum of the digits of k in
its usual decimal representation. Thus d(42) = 4+2 = 6. For a positive
integer n, define S(n) as the number of positive integers k < 10n
with the following properties : k is divisible by 23 and d(k) = 23. You
are given that S(9) = 263626 and S(42) = 6377168878570056. Find S(1112)
and give your answer mod 109.