cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A326346 Total number of partitions in the partitions of compositions of n.

Original entry on oeis.org

0, 1, 4, 14, 47, 151, 474, 1457, 4414, 13210, 39155, 115120, 336183, 976070, 2819785, 8110657, 23239662, 66362960, 188930728, 536407146, 1519205230, 4293061640, 12106883585, 34079016842, 95762829405, 268670620736, 752676269695, 2105751165046, 5883798478398
Offset: 0

Views

Author

Alois P. Heinz, Sep 11 2019

Keywords

Examples

			a(3) = 14 = 1+1+1+2+2+2+2+3 counts the partitions in 3, 21, 111, 2|1, 11|1, 1|2, 1|11, 1|1|1.
		

Crossrefs

Programs

  • Maple
    b:= proc(n) option remember; `if`(n=0, [1, 0], (p-> p+
          [0, p[1]])(add(combinat[numbpart](j)*b(n-j), j=1..n)))
        end:
    a:= n-> b(n)[2]:
    seq(a(n), n=0..32);
  • Mathematica
    b[n_] := b[n] = If[n==0, {1, 0}, Function[p, p + {0, p[[1]]}][Sum[ PartitionsP[j] b[n-j], {j, 1, n}]]];
    a[n_] := b[n][[2]];
    a /@ Range[0, 32] (* Jean-François Alcover, Dec 05 2020, after Alois P. Heinz *)

Formula

a(n) = Sum_{k=1..n} k * A060642(n,k).
a(n) ~ c * d^n * n, where d = A246828 = 2.69832910647421123126399866618837633... and c = 0.171490233695958246364725709205670983251448838158816... - Vaclav Kotesovec, Sep 14 2019