A393219 Row 3 of A372254.

230, 1902, 15402, 122190, 951546, 7290942, 55093962, 411436590, 3042112026, 22304883102, 162387026922, 1175201358990, 8462293710906, 60676240696062, 433500088316682, 3087729112881390, 21936639547140186, 155507573069193822, 1100339228646067242, 7773491027771603790

Offset

0,1

Links

Table of n, a(n) for n=0..19.

Formula

a(n) ~ 720 * 7^n.

Mathematica

g[n_] := g[n] = If[n == 0, 1, Sum[Expand[x*g[n-j]]*Binomial[n-1, j-1], {j, 1, n}]]; A[n_, k_] := A[n, k] = Module[{q, l, b}, {q, l} = {-1, {n, n, k}}; b[n0_, j_] := b[n0, j] = If[j == 1, Product[q-i, {i, 0, n0-1}]*(q-n0)^l[[1]], Sum[b[n0 + m, j-1]*Coefficient[g[l[[j]]], x, m], {m, 0, l[[j]]}]]; Abs[b[0, 3]]]; Table[A[3, n], {n, 0, 20}] (* after Jean-François Alcover *)

Crossrefs

Cf. A372254.

Sequence in context: A291617 A304389 A211711 * A211716 A251445 A251283

Adjacent sequences: A393216 A393217 A393218 * A393220 A393221 A393222

Keyword

nonn

Author

Vaclav Kotesovec, Feb 06 2026

Status

approved