A127135 Derived from the central terms (A127134) of triangle A127126; a(n) = A127126(2n,n)/(n+1).

1, 1, 6, 71, 1336, 35233, 1205605, 50905881, 2561801682, 149816972193, 9988787022964, 748036456826960, 62173668375158492, 5679720951862607185, 565666934647950245036, 61000592050512159666215

Offset: 0

Author

Paul D. Hanna, Jan 05 2007

Keywords

• nonn

Links

• G. C. Greubel, Table of n, a(n) for n = 0..50

Crossrefs

Cf. A127126, A127127, A127128, A127129, A127130, A127131, A127132, A127133, A127134.

Programs

Mathematica

T[n_, k_]:= T[n, k]= If[k==n, 1, Coefficient[(1 +x*Sum[x^(r-k-1)*Sum[T[r, c], {c,k+1,r}], {r,k+1,n}] +x^(n+1))^(k+1), x, n-k]]; Table[T[2*n, n]/(n+1), {n, 0, 20}] (* G. C. Greubel, Jan 28 2020 *)

Formula

a(n) = A127134(n)/(n+1).