152456domain: NAppears in sequencesa(n) = T(2n,n-1), where T is defined in A026022.at n=9A026030Number of cyclic subgroups of the group C_n x C_n x C_n x C_n, where C_n is the cyclic group of order n.at n=35A280184Expansion of f(t) = F^{[-1]}(t)/t, where F(x) = x/(1 - x^2 - x^3).at n=20A319201