a(n) = ( (9 + 2*sqrt(2))^n - (9 - 2*sqrt(2))^n )/(4*sqrt(2)).

A154350

a(n) = ( (9 + 2*sqrt(2))^n - (9 - 2*sqrt(2))^n )/(4*sqrt(2)).

Terms

    a(0) =1a(1) =18a(2) =251a(3) =3204a(4) =39349a(5) =474390a(6) =5666543a(7) =67367304a(8) =798953833a(9) =9463355802a(10) =112016774627

External references