53761domain: NAppears in sequencesStrong pseudoprimes to base 60.at n=21A020286Numbers k such that k, k+2, k+4, k+6, k+8, k+10 are semiprimes.at n=21A092128a(n) = (2*n^3 + 5*n^2 - 17*n)/2.at n=36A162259a(n) = n! * Sum_{k=0..floor(n/5)} n^k / (k! * (n-5*k)!).at n=8A362323