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A294237
Sum of the larger parts of the partitions of n into two parts with smaller part nonsquarefree.
1
0, 0, 0, 0, 0, 0, 0, 4, 5, 6, 7, 8, 9, 10, 11, 20, 22, 33, 36, 39, 42, 45, 48, 63, 67, 71, 75, 79, 83, 87, 91, 111, 116, 121, 126, 149, 155, 161, 167, 193, 200, 207, 214, 221, 228, 235, 242, 273, 281, 314, 323, 332, 341, 377, 387, 425, 436, 447, 458, 469
OFFSET
1,8
FORMULA
a(n) = Sum_{i=1..floor(n/2)} (n - i) * (1 - mu(i)^2), where mu is the Möbius function (A008683).
MATHEMATICA
Table[Sum[(n - k) (1 - MoebiusMu[k]^2), {k, Floor[n/2]}], {n, 80}]
Table[Total[Select[IntegerPartitions[n, {2}], !SquareFreeQ[#[[2]]]&][[All, 1]]], {n, 60}] (* Harvey P. Dale, Jun 20 2021 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Oct 25 2017
STATUS
approved