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%I #17 Dec 26 2020 12:41:46
%S 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,
%T 59,67,60,68,61,70,79,89,82,93,104,116,109,122,135,149,142,157,149,
%U 163,154,169,184,199,214,230,219,235,251,268,285,303,292,311,299
%N Sum of the smaller parts of the partitions of n into two parts with larger part squarefree.
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F a(n) = Sum_{i=1..floor(n/2)} i * mu(n-i)^2, where mu is the Möbius function (A008683).
%t Table[Sum[i*MoebiusMu[n - i]^2, {i, Floor[n/2]}], {n, 80}]
%t Table[Total[Select[IntegerPartitions[n,{2}],SquareFreeQ[#[[1]]]&][[All,2]]],{n,70}] (* _Harvey P. Dale_, Dec 26 2020 *)
%Y Cf. A008683, A008966, A294146.
%K nonn,easy
%O 1,4
%A _Wesley Ivan Hurt_, Oct 23 2017