Primality proof for n = 231503:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=115751.html>115751 is prime.</a>
<br>b^((n-1)/115751)-1 mod n = 3, which is a unit, inverse 77168.
<p>(115751) divides n-1.
<p>(115751)^2 > n.
<p>n is prime by Pocklington's theorem.