EE29
      +---------
EC508 | E5D31C3E
       -EC508
        =====
         EA7BC
        -EC508
         =====
          90243
         -9E51B
          =====
           4A3BE
          -C57C1
           =====
           E234C

base: 15
letters: 0123456789ABCDE
difficulty: hard
missing: 6