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%I #10 Sep 17 2020 16:38:17
%S 0,0,1,2,4,2,9,8,16,8,16,18,27,18,40,32,55,32,72,32,91,32,112,54,135,
%T 54,135,80,135,80,164,110,195,110,228,144,263,144,300,182,339,182,380,
%U 224,423,224,423,270,470,270,470,270,521,270,574,270,629,270,686
%N Sum of the squarefree differences |q-p| of the parts in the partitions of n into two distinct parts (p,q) where p < q.
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F a(n) = Sum_{i=1..floor((n-1)/2)} (n-2*i) * mu(n-2*i)^2, where mu is the Möbius function (A008683).
%t Table[Sum[(n - 2 i) MoebiusMu[n - 2 i]^2, {i, Floor[(n - 1)/2]}], {n, 100}]
%Y Cf. A008683, A303205.
%K nonn,easy
%O 1,4
%A _Wesley Ivan Hurt_, Apr 19 2018