Take b = 2.

b^(n-1) mod n = 1.

151 is prime.

b^((n-1)/151)-1 mod n = 124290, which is a unit, inverse 94632.

83 is prime.

b^((n-1)/83)-1 mod n = 15625, which is a unit, inverse 69882.

(83 * 151) divides n-1.

(83 * 151)^2 > n.

n is prime by Pocklington's theorem.