A374892 Obverse convolution (n)**(n(n+1)/2); see Comments.

0, 1, 12, 216, 5600, 198000, 9144576, 533653120, 38339288064, 3320915760000, 340950896000000, 40905397939101696, 5666507699182387200, 897094997540641908736, 160875919414586880000000, 32426573960663769600000000, 7296186062362650316241371136

Offset

0,3

Comments

See A374848 for the definition of obverse convolution and a guide to related sequences.

Links

Table of n, a(n) for n=0..16.

Formula

a(n) ~ n^(2*n+1) / (2^n * exp(2*n + 2 - Pi*sqrt(2*n))). - Vaclav Kotesovec, Sep 15 2024

Mathematica

s[n_] := n; t[n_] := n (n + 1)/2;
u[n_] := Product[s[k] + t[n - k], {k, 0, n}]
Table[u[n], {n, 0, 20}]

Crossrefs

Cf. A000027, A000217, A374848.

Sequence in context: A082165 A006689 A009176 * A087585 A297503 A214512

Adjacent sequences: A374889 A374890 A374891 * A374893 A374894 A374895

Keyword

nonn

Author

Clark Kimberling, Sep 14 2024

Status

approved