a(n) = ((4+3*sqrt(2))*(3+sqrt(2))^n + (4-3*sqrt(2))*(3-sqrt(2))^n)/4.

A164033

a(n) = ((4+3*sqrt(2))*(3+sqrt(2))^n + (4-3*sqrt(2))*(3-sqrt(2))^n)/4.

Terms

    a(0) =2a(1) =9a(2) =40a(3) =177a(4) =782a(5) =3453a(6) =15244a(7) =67293a(8) =297050a(9) =1311249a(10) =5788144a(11) =25550121a(12) =112783718a(13) =497851461a(14) =2197622740a(15) =9700776213a(16) =42821298098a(17) =189022355097a(18) =834385043896

External references