Primality proof for n = 12457521438949:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=115347420731.html>115347420731 is prime.</a>
<br>b^((n-1)/115347420731)-1 mod n = 9361982794440, which is a unit, inverse 26704078487.
<p>(115347420731) divides n-1.
<p>(115347420731)^2 > n.
<p>n is prime by Pocklington's theorem.