Primality proof for n = 4093:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=31.html>31 is prime.</a>
<br>b^((n-1)/31)-1 mod n = 1147, which is a unit, inverse 1877.
<p><a href=11.html>11 is prime.</a>
<br>b^((n-1)/11)-1 mod n = 99, which is a unit, inverse 1323.
<p>(11 * 31) divides n-1.
<p>(11 * 31)^2 > n.
<p>n is prime by Pocklington's theorem.