621443domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumbers k such that (2^k + 1)^2 - 2 = 4^k + 2^(k+1) - 1 is prime.at n=49A091513Primes p such that p^10 - 1 has 256 divisors.at n=17A342066Prime numbersat n=50722