Primality proof for n = 303767:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=151883.html>151883 is prime.</a>
<br>b^((n-1)/151883)-1 mod n = 3, which is a unit, inverse 101256.
<p>(151883) divides n-1.
<p>(151883)^2 > n.
<p>n is prime by Pocklington's theorem.