5256091domain: NAppears in sequencesStrong pseudoprimes to base 2 and 5.at n=3A215568Composite numbers n such that n == 3 (mod 8) and 2^((n-1)/2) == -1 (mod n).at n=12A244628Fermat pseudoprimes to base 2 that are octadecagonal.at n=9A322160