48544121domain: NPropertiesPrimalityPrimeyesAppears in sequencesSecond prime factor, if it exists, of Mersenne numbers.at n=10A089158Primes p such that (p-1)/ord(2,p) > (q-1)/ord(2,q) for odd primes q < p.at n=27A226216Prime factors of 2^A054723(n)-1, ordered by increasing n, then by increasing size of the factors.at n=25A244453Prime numbersat n=2918851