Primality proof for n = 13309:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=1109.html>1109 is prime.</a>
<br>b^((n-1)/1109)-1 mod n = 4095, which is a unit, inverse 13296.
<p>(1109) divides n-1.
<p>(1109)^2 > n.
<p>n is prime by Pocklington's theorem.