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A049790 Triangular array T read by rows: T(n,k) = Sum_{j=1..k} floor(n/floor(k/j)).

%I A049790 #14 Sep 08 2022 08:44:58
%S A049790 1,2,3,3,4,7,4,6,9,11,5,7,11,13,18,6,9,14,16,22,24,7,10,16,18,25,27,
%T A049790 34,8,12,18,22,29,31,39,43,9,13,21,24,32,35,44,47,55,10,15,23,27,37,
%U A049790 39,49,53,61,66,11,16,25,29,40,42,53,57,66,71,82,12,18,28,33,44,48,59,64,74,79,91,94
%N A049790 Triangular array T read by rows: T(n,k) = Sum_{j=1..k} floor(n/floor(k/j)).
%H A049790 G. C. Greubel, <a href="/A049790/b049790.txt">Rows n = 1..100 of triangle, flattened</a>
%e A049790 Triangle begins as:
%e A049790   1;
%e A049790   2,  3;
%e A049790   3,  4,  7;
%e A049790   4,  6,  9, 11;
%e A049790   5,  7, 11, 13, 18;
%e A049790   6,  9, 14, 16, 22, 24;
%e A049790   7, 10, 16, 18, 25, 27, 34;
%e A049790   8, 12, 18, 22, 29, 31, 39, 43;
%p A049790 seq(seq( add(floor(n/floor(k/j)), j=1..k), k=1..n), n=1..15); # _G. C. Greubel_, Dec 09 2019
%t A049790 Table[Sum[Floor[n/Floor[k/j]], {j, k}], {n, 15}, {k, n}]//Flatten (* _G. C. Greubel_, Dec 09 2019 *)
%o A049790 (PARI) T(n,k) = sum(j=1,k, n\(k\j));
%o A049790 for(n=1, 15, for(k=1, n, print1(T(n,k), ", "))) \\ _G. C. Greubel_, Dec 09 2019
%o A049790 (Magma) [(&+[Floor(n/Floor(k/j)): j in [1..k]]): k in [1..n], n in [1..15]]; // _G. C. Greubel_, Dec 09 2019
%o A049790 (Sage) [[sum(floor(n/floor(k/j)) for j in (1..k)) for k in (1..n)] for n in (1..15)] # _G. C. Greubel_, Dec 09 2019
%o A049790 (GAP) Flat(List([1..15], n-> List([1..n], k-> Sum([1..k], j-> Int(n/Int(k/j)) )))); # _G. C. Greubel_, Dec 09 2019
%Y A049790 Cf. A049791, A049792, A049793, A049794, A049795, A049796.
%K A049790 nonn,tabl
%O A049790 1,2
%A A049790 _Clark Kimberling_