Primality proof for n = 13830319:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=256117.html>256117 is prime.</a>
<br>b^((n-1)/256117)-1 mod n = 3741164, which is a unit, inverse 2762072.
<p>(256117) divides n-1.
<p>(256117)^2 > n.
<p>n is prime by Pocklington's theorem.