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.

A332626 Sum of least integers of prime signatures over all partitions of n into distinct parts.

Original entry on oeis.org

1, 2, 4, 20, 40, 152, 664, 1760, 5680, 24752, 138064, 356480, 1568320, 5886752, 32781664, 266420000, 726928960, 3135277952, 16299729664, 81402739520, 640678081600, 7084434124352, 18897678264064, 92846198695040, 464088929482240, 3347512310365952
Offset: 0

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Author

Alois P. Heinz, Feb 17 2020

Keywords

Examples

			a(5) = 2^5 + 2^4*3^1 + 2^3*3^2 = 32 + 48 + 72 = 152.
		

Crossrefs

Row sums of A328524.

Programs

  • Maple
    b:= proc(n, i, j) option remember; `if`(i*(i+1)/2 b(n$2, 1):
    seq(a(n), n=0..30);
  • Mathematica
    b[n_, i_, j_] := b[n, i, j] = If[i(i+1)/2 < n, 0, If[n == 0, 1, b[n, i - 1, j] + Prime[j]^i b[n - i, Min[n - i, i - 1], j + 1]]];
    a[n_] := b[n, n, 1];
    a /@ Range[0, 30] (* Jean-François Alcover, May 04 2020, after Maple *)

Formula

a(n) = Sum_{k=1..A000009(n)} A328524(n,k).