810C
      +---------
A9CB0 | 53A0BE70
       -63A03
        =====
        CDDD1E
       - 01541
        ======
         84F7F7
        -8487D7
         ======
           6DFD0
          -A9CB0
           =====
           8468D

base: 16
letters: 0123456789ABCDEF
difficulty: hard
missing: 2