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.

A294145 Sum of the smaller parts of the partitions of n into two parts with larger part squarefree.

Original entry on oeis.org

0, 1, 1, 3, 2, 4, 3, 6, 9, 12, 10, 14, 11, 15, 12, 17, 22, 28, 34, 41, 37, 44, 40, 48, 56, 64, 59, 67, 60, 68, 61, 70, 79, 89, 82, 93, 104, 116, 109, 122, 135, 149, 142, 157, 149, 163, 154, 169, 184, 199, 214, 230, 219, 235, 251, 268, 285, 303, 292, 311, 299
Offset: 1

Views

Author

Wesley Ivan Hurt, Oct 23 2017

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Sum[i*MoebiusMu[n - i]^2, {i, Floor[n/2]}], {n, 80}]
    Table[Total[Select[IntegerPartitions[n,{2}],SquareFreeQ[#[[1]]]&][[All,2]]],{n,70}] (* Harvey P. Dale, Dec 26 2020 *)

Formula

a(n) = Sum_{i=1..floor(n/2)} i * mu(n-i)^2, where mu is the Möbius function (A008683).