357975249026domain: NAppears in sequencesa(n) = [ C(2n,n)/n ].at n=22A024498Number of orbits of length n under the map whose periodic points are counted by A000984.at n=22A060165Erroneous version of A177454.at n=7A078464a(n) = (binomial(2*p,p) - 2)/p, where p = prime(n).at n=8A177454