Pisot sequence T(2,9), a(n) = floor(a(n-1)^2/a(n-2)).

Terms

a(0) =2a(1) =9a(2) =40a(3) =177a(4) =783a(5) =3463a(6) =15315a(7) =67730a(8) =299533a(9) =1324671a(10) =5858296a(11) =25908042a(12) =114577112a(13) =506711954a(14) =2240910072a(15) =9910320668a(16) =43827932664a(17) =193826995709a(18) =857190882207