a(n) = C(n)*C(n+2) - C(n+1)^2 where C() are the Catalan numbers A000108.
A005700
a(n) = C(n)*C(n+2) - C(n+1)^2 where C() are the Catalan numbers A000108.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =14a(4) =84a(5) =594a(6) =4719a(7) =40898a(8) =379236a(9) =3711916a(10) =37975756a(11) =403127256a(12) =4415203280a(13) =49671036900a(14) =571947380775
External references
- oeis: A005700