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Triangle T(n,k) = floor(n^2/k) for 1 <= k <= n^2, read by rows.
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%I #20 Sep 08 2022 08:46:17

%S 1,4,2,1,1,9,4,3,2,1,1,1,1,1,16,8,5,4,3,2,2,2,1,1,1,1,1,1,1,1,25,12,8,

%T 6,5,4,3,3,2,2,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,36,18,12,9,7,6,5,4,4,3,3,

%U 3,2,2,2,2,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,49,24,16,12,9,8,7,6

%N Triangle T(n,k) = floor(n^2/k) for 1 <= k <= n^2, read by rows.

%H Jason Kimberley, <a href="/A277646/b277646.txt">Table of n, a(n) for n = 1..10416 (the first 31 rows of the triangle)</a>

%F T(n,k) = A010766(n^2,k).

%e The first five rows of the triangle are:

%e 1;

%e 4, 2, 1, 1;

%e 9, 4, 3, 2, 1, 1, 1, 1, 1;

%e 16, 8, 5, 4, 3, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1;

%e 25, 12, 8, 6, 5, 4, 3, 3, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1;

%t Table[Floor[n^2/k], {n, 7}, {k, n^2}] // Flatten (* _Michael De Vlieger_, Nov 24 2016 *)

%o (Magma)

%o A277646:=func<n,k|n^2 div k>;

%o [A277646(n,k):k in[1..n^2],n in[1..7]];

%Y Cf. Related triangles: A010766, A277647, A277648.

%Y Rows of this triangle (with infinite trailing zeros):

%Y T(1,k) = A000007(k-1),

%Y T(2,k) = A033324(k),

%Y T(3,k) = A033329(k),

%Y T(4,k) = A033336(k),

%Y T(5,k) = A033345(k),

%Y T(6,k) = A033356(k),

%Y T(7,k) = A033369(k),

%Y T(8,k) = A033384(k),

%Y T(9,k) = A033401(k),

%Y T(10,k) = A033420(k),

%Y T(100,k) = A033422(k),

%Y T(10^3,k) = A033426(k),

%Y T(10^4,k) = A033424(k).

%Y Columns of this triangle:

%Y T(n,1) = A000290(n),

%Y T(n,2) = A007590(n),

%Y T(n,3) = A000212(n),

%Y T(n,4) = A002620(n),

%Y T(n,5) = A118015(n),

%Y T(n,6) = A056827(n),

%Y T(n,7) = A056834(n),

%Y T(n,8) = A130519(n+1),

%Y T(n,9) = A056838(n),

%Y T(n,10)= A056865(n),

%Y T(n,12)= A174709(n+2).

%K nonn,tabf,easy

%O 1,2

%A _Jason Kimberley_, Nov 09 2016