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

A161939

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

Terms

    a(0) =3a(1) =14a(2) =70a(3) =364a(4) =1932a(5) =10360a(6) =55832a(7) =301616a(8) =1631280a(9) =8827616a(10) =47783008a(11) =258677440a(12) =1400457408a(13) =7582175104a(14) =41050997120a(15) =222257525504

External references