For n>1, a(n) = 2*a(n-1) + 15*a(n-2); a(0)=1, a(1)=1.

Terms

a(0) =1a(1) =1a(2) =17a(3) =49a(4) =353a(5) =1441a(6) =8177a(7) =37969a(8) =198593a(9) =966721a(10) =4912337a(11) =24325489a(12) =122336033a(13) =609554401a(14) =3054149297a(15) =15251614609a(16) =76315468673a(17) =381405156481