Procedure isPrime(v.i)
  If     v <= 1    : ProcedureReturn #False
  ElseIf v < 4     : ProcedureReturn #True
  ElseIf v % 2 = 0 : ProcedureReturn #False
  ElseIf v < 9     : ProcedureReturn #True
  ElseIf v % 3 = 0 : ProcedureReturn #False
  Else
    Protected r = Round(Sqr(v), #PB_Round_Down)
    Protected f = 5
    While f <= r
      If v % f = 0 Or v % (f + 2) = 0
        ProcedureReturn #False
      EndIf
      f + 6
    Wend
  EndIf
  ProcedureReturn #True
EndProcedure

Procedure paresDePrimos(limite.d)
  p1.i = 0
  p2.i = 1
  p3.i = 1
  count.i = 0
  For i.i = 5 To limite
    p3 = p2
    p2 = p1
    p1 = isPrime(i)
    If p3 And p1
       count + 1
    EndIf
  Next i
  ProcedureReturn count
EndProcedure

OpenConsole()
n.i = 1
For i.i = 1 To 6
  n = n * 10
  PrintN("pares de primos gemelos por debajo de < " + Str(n) + " : " + Str(paresDePrimos(n)))
Next i
PrintN(#CRLF$ + "--- terminado, pulsa RETURN---"): Input()
CloseConsole()
End