100 PROGRAM "PerfectN.bas"
110 FOR X=1 TO 10000
120   IF PERFECT(X) THEN PRINT X;
130 NEXT
140 DEF PERFECT(N)
150   IF N<2 OR MOD(N,2)<>0 THEN LET PERFECT=0:EXIT DEF
160   LET S=1
170   FOR I=2 TO SQR(N)
180     IF MOD(N,I)=0 THEN LET S=S+I+N/I
190   NEXT
200   LET PERFECT=N=S
210 END DEF