83381domain: NAppears in sequencesStrong pseudoprimes to base 85.at n=31A020311Numbers n such that 7^n + 12 is prime.at n=14A152213Odd k for which abs(2^m - k) is nonprime for all m < k.at n=24A263865Indices of centered 11-gonal numbers (A060544) that are also 11-gonal numbers (A051682).at n=4A280072