1649
      +---------
73747 | 90DC97A6
       -73747
        =====
        22A727
       -3B5306
        ======
         7A869A
        -C9AC7E
         ======
          243366
         -2902E0
          ======
           10481

base: 15
letters: 0123456789ABCDE
difficulty: medium
missing: 1