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.

A320610 Number of parts in all partitions of n in which no part occurs more than seven times.

Original entry on oeis.org

1, 3, 6, 12, 20, 35, 54, 78, 119, 173, 245, 347, 480, 657, 894, 1193, 1588, 2097, 2745, 3563, 4612, 5916, 7556, 9609, 12150, 15286, 19177, 23924, 29757, 36876, 45533, 56026, 68758, 84080, 102556, 124735, 151315, 183059, 220998, 266101, 319720, 383306, 458569
Offset: 1

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Author

Alois P. Heinz, Oct 17 2018

Keywords

Crossrefs

Column k=7 of A210485.
Cf. A261775.

Programs

  • Maple
    b:= proc(n, i) option remember; `if`(n=0, [1, 0], `if`(7*i*(i+1)/2 [0, l[1]*j]+l)(b(n-i*j, min(n-i*j, i-1))), j=0..min(n/i, 7))))
        end:
    a:= n-> b(n$2)[2]:
    seq(a(n), n=1..50);
  • Mathematica
    Table[Length[Flatten[Select[IntegerPartitions[n], Max[Tally[#][[All, 2]]] <= 7 &]]], {n, 43}] (* Robert Price, Jul 31 2020 *)

Formula

a(n) ~ 3^(5/4) * log(2) * exp(Pi*sqrt(7*n/3)/2) / (2^(3/2) * 7^(1/4) * Pi * n^(1/4)). - Vaclav Kotesovec, Oct 18 2018