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%I #8 May 28 2021 05:22:18
%S 1,6,14,31,47,81,103,153,195,260,299,401,453,542,643,761,834,999,1078,
%T 1266,1397,1548,1650,1932,2068,2257,2444,2707,2831,3203,3331,3629,
%U 3873,4128,4375,4830,5017,5309,5574,6066,6266,6756,6971,7416,7858,8177,8431,9140,9418
%N a(n) = Sum_{k=1..n} k*[ (n/k)*[ n/k ] ].
%t Table[Sum[k*Floor[n/k*Floor[n/k]], {k,1,n}], {n,1,50}] (* _Vaclav Kotesovec_, May 28 2021 *)
%K nonn
%O 1,2
%A _Clark Kimberling_