The clue says that p > 304, but the algorithm says that p must be a prime number, so we take the first prime number greater than 304. But p must also satisfy the formula p = 2^k * q + 1, where q is also a prime. My guess is that p = 317, because then you would have 317 = 2^k * q + 1 => 2^k * q = 316 an remember that q must be a prime, so you have 2^2 * 79 => q=79 and 79 is a prime number...