A127130 Column 3 of triangle A127126.

1, 4, 30, 284, 3217, 42100, 621936, 10206956, 183946656, 3608229588, 76499111202, 1742909621024, 42465280193704, 1101811478508828, 30331386700718440, 883010853509597608, 27105284242369828508, 874996700615422755068

Offset: 3

Author

Paul D. Hanna, Jan 05 2007

Keywords

• nonn

Comments

Self-convolution 4th power of A127133.

Links

• G. C. Greubel, Table of n, a(n) for n = 3..80

Crossrefs

Cf. A127126; A127133; other columns: A127127, A127128, A127129.

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[n, 3], {n, 3, 20}] (* G. C. Greubel, Jan 28 2020 *)