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

Terms

a(0) =0a(1) =1a(2) =2a(3) =19a(4) =68a(5) =421a(6) =1862a(7) =10039a(8) =48008a(9) =246601a(10) =1213322a(11) =6125659a(12) =30451148a(13) =152787181a(14) =762341582a(15) =3816490879a(16) =19068105488a(17) =95383574161a(18) =476788730642