G.f. A(x) satisfies A(x) = (1 + 2 * x * A(x)^3) / (1 - x).
A348912
G.f. A(x) satisfies A(x) = (1 + 2 * x * A(x)^3) / (1 - x).
Terms
- a(0) =1a(1) =3a(2) =21a(3) =201a(4) =2217a(5) =26535a(6) =335001a(7) =4391553a(8) =59203137a(9) =815580507a(10) =11430639165a(11) =162470033625
External references
- oeis: A348912