Pisot sequence T(4,9), a(n) = floor(a(n-1)^2/a(n-2)).

Terms

a(0) =4a(1) =9a(2) =20a(3) =44a(4) =96a(5) =209a(6) =455a(7) =990a(8) =2154a(9) =4686a(10) =10194a(11) =22176a(12) =48241a(13) =104942a(14) =228287a(15) =496607a(16) =1080300a(17) =2350043a(18) =5112193a(19) =11120867a(20) =24191904a(21) =52626132a(22) =114480851a(23) =249037213a(24) =541745915a(25) =1178493097a(26) =2563648273a(27) =5576861234a(28) =12131688091a(29) =26390804748