Primality proof for n = 2039:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=1019.html>1019 is prime.</a>
<br>b^((n-1)/1019)-1 mod n = 3, which is a unit, inverse 680.
<p>(1019) divides n-1.
<p>(1019)^2 > n.
<p>n is prime by Pocklington's theorem.