Primality proof for n = 1618781663:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=22679.html>22679 is prime.</a>
<br>b^((n-1)/22679)-1 mod n = 256029465, which is a unit, inverse 1269146842.
<p><a href=401.html>401 is prime.</a>
<br>b^((n-1)/401)-1 mod n = 660993085, which is a unit, inverse 107698225.
<p>(401 * 22679) divides n-1.
<p>(401 * 22679)^2 > n.
<p>n is prime by Pocklington's theorem.