Prime Number Search

[SlideRule]

A excerpt from Interface Age, 1982-03, pg.12

… Instead of finding the PRIME numbers, it is quicker to search for the numbers that are NOT PRIME. The program to do this is listed here. …
      10 PRINT "Starting."
      20 DEFINT A-Z
      30 DIM A(1000)
      40 FOR I=2 TO 500
      50 FOR J=2 TO 32
      60 IF I*J>1000 GOTO 90
      70 A(I*J)=1
      80 NEXT J
      90 NEXT I
     100 FOR I=1 TO 1000
     110 IF A(I)=0 THEN PRINT I;
     120 NEXT I
     130 PRINT "Finished."
  Although the problem is trivial, the exercise emphasizes the importance of the approach adopted - a fairly simple revision of basic ideas …

BEST!
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error corrected