a(n) = 2^n * C(n+1), where C(n) = A000108(n) Catalan numbers.
A003645
a(n) = 2^n * C(n+1), where C(n) = A000108(n) Catalan numbers.
Terms
- a(0) =1a(1) =4a(2) =20a(3) =112a(4) =672a(5) =4224a(6) =27456a(7) =183040a(8) =1244672a(9) =8599552a(10) =60196864a(11) =426008576a(12) =3042918400a(13) =21909012480a(14) =158840340480
External references
- oeis: A003645