Primality proof for n = 34123:
Take b = 2.
b^(n-1) mod n = 1.
47 is prime.
b^((n-1)/47)-1 mod n = 30028, which is a unit, inverse 5683.
11 is prime.
b^((n-1)/11)-1 mod n = 30210, which is a unit, inverse 8328.
(11^2 * 47) divides n-1.
(11^2 * 47)^2 > n.
n is prime by Pocklington's theorem.