4783698domain: NAppears in sequencesSums of two distinct powers of 9.at n=24A038487Sums of two powers of 9.at n=31A055260Dirichlet g.f.: Product_{k>=2} 1 / (1 - k^(-s))^(3^(k-1)).at n=14A344247Dirichlet g.f.: Product_{k>=2} (1 + k^(-s))^(3^(k-1)).at n=14A344266