Take b = 2.

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

151 is prime.

b^((n-1)/151)-1 mod n = 82141, which is a unit, inverse 230027.

5 is prime.

b^((n-1)/5)-1 mod n = 61938, which is a unit, inverse 19757.

(5^2 * 151) divides n-1.

(5^2 * 151)^2 > n.

n is prime by Pocklington's theorem.