a(n) = L(n)*L(n+1), where L = A000032 (Lucas numbers).

Terms

a(0) =2a(1) =3a(2) =12a(3) =28a(4) =77a(5) =198a(6) =522a(7) =1363a(8) =3572a(9) =9348a(10) =24477a(11) =64078a(12) =167762a(13) =439203a(14) =1149852a(15) =3010348a(16) =7881197a(17) =20633238a(18) =54018522a(19) =141422323a(20) =370248452a(21) =969323028a(22) =2537720637a(23) =6643838878a(24) =17393796002a(25) =45537549123a(26) =119218851372a(27) =312119004988a(28) =817138163597