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.

A327118 Total number of colors in all colored integer partitions of n using all colors of an initial color palette such that a color pattern for part i has i distinct colors in increasing order.

Original entry on oeis.org

0, 1, 5, 24, 129, 752, 4796, 33117, 246336, 1961233, 16626100, 149376533, 1416602126, 14130107135, 147781380186, 1616110614723, 18434515499407, 218849548323400, 2698686223271769, 34504328470389166, 456669361749612835, 6247290917385938422, 88216873775207493056
Offset: 0

Views

Author

Alois P. Heinz, Sep 13 2019

Keywords

Crossrefs

Cf. A327117.

Programs

  • Maple
    C:= binomial:
    b:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0, add(
          b(n-i*j, min(n-i*j, i-1), k)*C(C(k, i)+j-1, j), j=0..n/i)))
        end:
    a:= n-> add(k*add(b(n$2, i)*(-1)^(k-i)*C(k, i), i=0..k), k=0..n):
    seq(a(n), n=0..25);
  • Mathematica
    b[n_, i_, k_] := b[n, i, k] = If[n == 0, 1, If[i < 1, 0, Sum[b[n - i j, Min[n - i j, i-1], k] Binomial[Binomial[k, i]+j-1, j], {j, 0, n/i}]]];
    a[n_] := Sum[k Sum[b[n, n, i](-1)^(k-i)Binomial[k, i], {i, 0, k}], {k, 0, n}];
    a /@ Range[0, 25] (* Jean-François Alcover, May 06 2020, after Maple *)

Formula

a(n) = Sum_{k=1..n} k * A327117(n,k).