YXE
      +---------
YJHYY | UYUEXLTM
       -UHXTMH
        ======
         EJTHHT
        -NLNTJL
         ======
          NULUYM
         -NXNJUX
          ======
           NMUXT

base: 11
letters: EHJLMNPTUXY
difficulty: intermediate
restrictions: no multiplication
missing: P