i = 42
counter = 0
while counter < 42
    if isPrime(i) then
        counter = counter + 1
        print "n = ", counter, chr$(9), i
        i = i + i - 1
    end if
    i = i + 1
wend
end

sub isPrime(v)
    if v < 2  return False
    if mod(v, 2) = 0  return v = 2
    if mod(v, 3) = 0  return v = 3
    d = 5
    while d * d <= v
        if mod(v, d) = 0 then return False else d = d + 2 : fi
    wend
    return True
end sub