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.

A343147 The number of partitions of the n-th primorial into distinct parts.

Original entry on oeis.org

1, 1, 4, 296, 884987529, 41144767887910339859917073881177514
Offset: 0

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Author

Alois P. Heinz, Apr 06 2021

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n) b(n):= `if`(n=0, 1, b(n-1)*ithprime(n)) end:
    g:= proc(n) option remember; `if`(n=0, 1, add(g(n-j)*add(
         `if`(d::odd, d, 0), d=numtheory[divisors](j)), j=1..n)/n)
        end:
    a:= n-> g(b(n)):
    seq(a(n), n=0..5);
  • Mathematica
    $RecursionLimit = 2^13;
    b[n_] := b[n] = If[n == 0, 1, b[n - 1]*Prime[n]];
    g[n_] := g[n] = If[n == 0, 1, Sum[g[n - j]*Sum[
         If[OddQ[d], d, 0], {d, Divisors[j]}], {j, 1, n}]/n];
    a[n_] := g[b[n]];
    Table[a[n], {n, 0, 5}] (* Jean-François Alcover, May 02 2022, after Alois P. Heinz *)

Formula

a(n) = A000009(A002110(n)).