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A049792 a(n) = Sum_{k=1..n} floor(n/floor(n/k)).

%I A049792 #20 Sep 08 2022 08:44:58
%S A049792 1,3,7,11,18,24,34,43,55,66,82,94,113,129,150,167,192,211,239,261,290,
%T A049792 315,349,374,410,440,478,509,552,583,629,665,711,750,802,838,893,937,
%U A049792 992,1036,1097,1141,1205,1255,1317,1370,1440
%N A049792 a(n) = Sum_{k=1..n} floor(n/floor(n/k)).
%H A049792 Ivan Neretin, <a href="/A049792/b049792.txt">Table of n, a(n) for n = 1..10000</a>
%F A049792 a(n) = A049790(n, n).
%F A049792 a(n) = A222548(n) - Sum_{i=1..n} floor(n/i)*floor(n/(i+1)). - _Ridouane Oudra_, Jun 22 2020
%F A049792 a(n) ~ (zeta(2) - 1) * n^2. - _Vaclav Kotesovec_, May 28 2021
%p A049792 seq( add(floor(n/floor(n/j)), j=1..n), n=1..60); # _G. C. Greubel_, Dec 10 2019
%t A049792 Table[Total[Table[Quotient[n, Quotient[n, k]], {k, n}]], {n, 47}] (* _Ivan Neretin_, Jul 29 2015 *)
%o A049792 (PARI) a(n) = sum(j=1,n, n\(n\j));
%o A049792 vector(60, n, a(n) ) \\ _G. C. Greubel_, Dec 10 2019
%o A049792 (Magma) [(&+[Floor(n/Floor(n/j)): j in [1..n]]): n in [1..60]]; // _G. C. Greubel_, Dec 10 2019
%o A049792 (Sage) [sum(floor(n/floor(n/j)) for j in (1..n)) for n in (1..60)] # _G. C. Greubel_, Dec 10 2019
%o A049792 (GAP) List([1..60], n-> Sum([1..n], j-> Int(n/Int(n/j)) )); # _G. C. Greubel_, Dec 10 2019
%Y A049792 Cf. A049790, A049791, A049793, A049794, A049795, A049796.
%K A049792 nonn
%O A049792 1,2
%A A049792 _Clark Kimberling_