Primality proof for n = 13481018963:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=196993.html>196993 is prime.</a>
<br>b^((n-1)/196993)-1 mod n = 11454426697, which is a unit, inverse 13232075911.
<p>(196993) divides n-1.
<p>(196993)^2 > n.
<p>n is prime by Pocklington's theorem.