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.

A235793 Sum of all parts of all overpartitions of n.

Original entry on oeis.org

2, 8, 24, 56, 120, 240, 448, 800, 1386, 2320, 3784, 6048, 9464, 14560, 22080, 32992, 48688, 71064, 102600, 146720, 207984, 292336, 407744, 564672, 776650, 1061424, 1442016, 1947904, 2617192, 3498720, 4654464, 6163584, 8126448, 10669472, 13952400, 18175896
Offset: 1

Views

Author

Omar E. Pol, Jan 18 2014

Keywords

Comments

The equivalent sequence for partitions is A066186.

Crossrefs

Programs

  • Maple
    b:= proc(n, i) option remember; `if`(n=0, [1, 0],
          `if`(i<1, [0$2], b(n, i-1)+add((l-> l+[0, l[1]*i*j])
           (2*b(n-i*j, i-1)), j=1..n/i)))
        end:
    a:= n-> b(n$2)[2]:
    seq(a(n), n=1..40);  # Alois P. Heinz, Jan 21 2014
  • Mathematica
    Table[n*Sum[PartitionsP[n-k]*PartitionsQ[k], {k, 0, n}], {n, 1, 40}] (* Jean-François Alcover, Oct 20 2016, after Vaclav Kotesovec *)

Formula

a(n) = n*A015128(n).
a(n) ~ exp(Pi*sqrt(n)) / 8. - Vaclav Kotesovec, May 19 2018