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