1415
      +---------
44C21 | AD8A4858
       -EED14
        =====
        2258B8
       -22244E
        ======
          31675
         -EED14
          =====
          0D25A8
         -08E2FD
          ======
           1A6D5

base: 16
letters: 0123456789ABCDEF
difficulty: hard
missing: 9