' version 18-01-2019
' compile with: fbc -s console

Function isprime(number As ULongInt) As UInteger

    If number Mod 2 = 0 Then Return 0
    If number Mod 3 = 0 Then Return 0
    Dim As UInteger i, max = Sqr(number)

    For i = 5 To max Step 2
        If number Mod i = 0 Then Return 0
    Next

    Return 1

End Function

' ------=< MAIN >=------

Dim As UInteger counter
Dim As ULongInt i

Print : Print
counter = 0
For i = 42 To &HFFFFFFFFFFFFFFFF    ' for next loop, loop maximum = 2^64-1
    If isprime(i) Then
        counter += 1
        Print Using "n =### ##################,"; counter; i
        If counter >= 42 Then Exit for
        i += i -1
    End If
Next

' empty keyboard buffer
While InKey <> "" : Wend
Print : Print "hit any key to end program"
Sleep
End