a(n) = Pell(n) * Sum_{d|n} 1/Pell(d), where Pell(n) = A000129(n).

Terms

a(0) =1a(1) =3a(2) =6a(3) =19a(4) =30a(5) =120a(6) =170a(7) =647a(8) =1183a(9) =3650a(10) =5742a(11) =24916a(12) =33462a(13) =121652a(14) =240756a(15) =746639a(16) =1136690a(17) =4707147a(18) =6625110a(19) =25882770a(20) =46565244a(21) =139849776a(22) =225058682a(23) =978088748a(24) =1356970471a(25) =4750318586a(26) =9182205852a(27) =29333908544a(28) =44560482150a(29) =188175715440