N% = 0
      REPEAT
        PRINT FN_tobase(N%, 8, 0)
        N% += 1
      UNTIL FALSE
      END

      REM Convert N% to string in base B% with minimum M% digits:
      DEF FN_tobase(N%, B%, M%)
      LOCAL D%, A$
      REPEAT
        D% = N% MOD B%
        N% DIV= B%
        IF D%<0 D% += B% : N% -= 1
        A$ = CHR$(48 + D% - 7*(D%>9)) + A$
        M% -= 1
      UNTIL (N%=FALSE OR N%=TRUE) AND M%<=0
      =A$