4AA3
      +---------
9BC0C | C3494749
       -85B8A
        =====
        978AC7
       -9CA3CB
        ======
         91C654
        -9CA3CB
         ======
           00839
          -71577
           =====
           99157

base: 13
letters: 0123456789ABC
difficulty: medium
missing: 2