RosettaCodeData/Task/Perfect-numbers/BBC-BASIC/perfect-numbers-1.basic

      FOR n% = 2 TO 10000 STEP 2
        IF FNperfect(n%) PRINT n%
      NEXT
      END

      DEF FNperfect(N%)
      LOCAL I%, S%
      S% = 1
      FOR I% = 2 TO SQR(N%)-1
        IF N% MOD I% = 0 S% += I% + N% DIV I%
      NEXT
      IF I% = SQR(N%) S% += I%
      = (N% = S%)