Overlay of Pell numbers: a(n)=A000129(n)+A000129(n-6).

Terms

a(0) =0a(1) =1a(2) =2a(3) =5a(4) =12a(5) =29a(6) =70a(7) =170a(8) =410a(9) =990a(10) =2390a(11) =5770a(12) =13930a(13) =33630a(14) =81190a(15) =196010a(16) =473210a(17) =1142430a(18) =2758070a(19) =6658570a(20) =16075210a(21) =38808990a(22) =93693190a(23) =226195370a(24) =546083930a(25) =1318363230a(26) =3182810390a(27) =7683984010a(28) =18550778410a(29) =44785540830