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%I #16 Sep 08 2022 08:44:48
%S 1,9,29,74,140,254,391,601,851,1183,1546,2058,2580,3244,3986,4876,
%T 5795,6959,8105,9540,11012,12692,14391,16546,18590,20966,23425,26255,
%U 28992,32344,35472,39173,42886,46974,51075,55963,60475,65602,70781,76696,82244,88826
%N a(n) = Sum_{k=1..n} floor((n/k) * floor((n/k) * floor(n/k))).
%F a(n) ~ zeta(3) * n^3. - _Vaclav Kotesovec_, May 28 2021
%t Total/@Table[Floor[n/k Floor[n/k Floor[n/k]]],{n,50},{k,n}] (* _Harvey P. Dale_, May 14 2013 *)
%t Table[Sum[Floor[n / k Floor[n / k Floor[n / k]]], {k, 1, n}], {n, 1, 50}] (* _Vincenzo Librandi_, Jul 28 2019 *)
%o (PARI) a(n) = sum(k=1, n, floor((n/k)*floor((n/k)*floor(n/k)))) \\ _Michel Marcus_, Mar 23 2013
%o (Magma) [&+[((n div k)*((n div k)*(n div k))): k in [1..n]]: n in [1..50]]; // _Vincenzo Librandi_, Jul 28 2019
%K nonn
%O 1,2
%A _Clark Kimberling_
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