Primality proof for n = 13759:
Take b = 2.
b^(n-1) mod n = 1.
2293 is prime. b^((n-1)/2293)-1 mod n = 63, which is a unit, inverse 1092.
(2293) divides n-1.
(2293)^2 > n.
n is prime by Pocklington's theorem.