Primality proof for n = 15823:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=293.html>293 is prime.</a>
<br>b^((n-1)/293)-1 mod n = 481, which is a unit, inverse 9178.
<p>(293) divides n-1.
<p>(293)^2 > n.
<p>n is prime by Pocklington's theorem.