A026934 a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A008288.

1, 6, 35, 196, 1093, 6090, 33991, 190152, 1066313, 5993422, 33759851, 190538380, 1077316493, 6101144722, 34603634063, 196524445840, 1117492252561, 6361505951382, 36251199646387, 206773994830164, 1180452564195797, 6744529721551450, 38563791929450071, 220652949570236760

Offset: 1

Author

Clark Kimberling

Keywords

• nonn

Links

• G. C. Greubel, Table of n, a(n) for n = 1..500

Crossrefs

Cf. A008288.

Programs

Mathematica

A008288[n_, k_]:= Binomial[n, k]*Hypergeometric2F1[-k, k-n, -n, -1];
A026934[n_]:= Sum[A008288[n, k]*A008288[n, k+1], {k, 0, n-1}];
Table[A026934[n], {n, 1, 40}] (* G. C. Greubel, May 25 2021 *)

Sage

@CachedFunction
def A008288(n,k): return sum(binomial(n-j, j)*binomial(n-2*j, k-j) for j in (0..k))
def A026934(n): return sum(A008288(n, k)*A008288(n, k+1) for k in (0..n-1))
[A026934(n) for n in (1..40)] # G. C. Greubel, May 25 2021

Extensions

More terms from Sean A. Irvine, Oct 17 2019