Primality proof for n = 13043:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=6521.html>6521 is prime.</a>
<br>b^((n-1)/6521)-1 mod n = 3, which is a unit, inverse 4348.
<p>(6521) divides n-1.
<p>(6521)^2 > n.
<p>n is prime by Pocklington's theorem.