269201domain: NPropertiesPrimalityPrimeyesAppears in sequencesa(n) = 3^n reduced modulo 2^n.at n=20A0023809^n mod 4^n.at n=10A139729Primes of the form 3^k mod 2^k, in the order in which they are found.at n=5A178985Prime numbersat n=23581