1468189domain: NPropertiesPrimalityPrimeyesAppears in sequencesa(n) = 1 + a(n-1) + a(n-2) + a(n-3) if n>=4; a(1) = a(2) = a(3) = 1.at n=24A248098Primes 6k + 1 at the end of the maximal gaps in A268925.at n=15A268927Primes 6k + 1 at the end of first-occurrence gaps in A330853.at n=33A330855Prime numbersat n=111917