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%I #12 Mar 16 2020 19:02:15
%S 1,3,6,6,11,34,41,41,41,66,77,77,90,117,152,152,169,169,188,188,225,
%T 436,459,459,459,672,672,672,701,936,967,967,1278,1495,1552,1552,1589,
%U 1808,2121,2121,2162,2399,2442,2442,2442,2665,2712,2712,2712,2712,3029,3029,3082,3082,3593,3593,3912
%N a(n) = Sum_{ i <= n, i squarefree} A080670(i).
%C A lower bound on A287881.
%H N. J. A. Sloane, <a href="/A287882/b287882.txt">Table of n, a(n) for n = 1..20000</a>
%t A080670 = Cases[Import["https://oeis.org/A080670/b080670.txt", "Table"], {_, _}][[All, 2]];
%t Accumulate[Table[If[SquareFreeQ[n], A080670[[n]], 0], {n, 57}] ] (* _Robert Price_, Mar 16 2020 *)
%Y Cf. A080670, A287881.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Jun 19 2017