67069domain: NAppears in sequencesStrong pseudoprimes to base 73.at n=21A020299Strong pseudoprimes to base 85.at n=27A020311Numbers k such that 335*2^k+1 is prime.at n=16A322960a(n) = Sum_{k=0..floor(n/3)} (n-3*k)^(3*k).at n=12A353017