cut (prime (nth_prime (max_prime_factor n))).
apply lt_O_nth_prime_n.apply prime_nth_prime.
cut (nth_prime (max_prime_factor n) \divides n).
cut (prime (nth_prime (max_prime_factor n))).
apply lt_O_nth_prime_n.apply prime_nth_prime.
cut (nth_prime (max_prime_factor n) \divides n).