168749965921domain: NAppears in sequencesFor p = prime(n), a(n) is the smallest prime q such that pq is a base-2 pseudoprime; that is, 2^(pq-1) = 1 mod pq; a(n) is 0 if no such prime exists.at n=32A085012Largest prime factor of 8^n + 1.at n=23A274905