Primality proof for n = 28817:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=1801.html>1801 is prime.</a>
<br>b^((n-1)/1801)-1 mod n = 7901, which is a unit, inverse 1065.
<p>(1801) divides n-1.
<p>(1801)^2 > n.
<p>n is prime by Pocklington's theorem.