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Triangle read by rows: T(n,m) is the number of integers k such that floor(n/k) = m, n >= 1, k = 1..n.
3

%I #18 Jan 15 2022 10:04:20

%S 1,1,1,2,0,1,2,1,0,1,3,1,0,0,1,3,1,1,0,0,1,4,1,1,0,0,0,1,4,2,0,1,0,0,

%T 0,1,5,1,1,1,0,0,0,0,1,5,2,1,0,1,0,0,0,0,1,6,2,1,0,1,0,0,0,0,0,1,6,2,

%U 1,1,0,1,0,0,0,0,0,1,7,2,1,1,0,1,0,0,0,0,0,0,1,7,3,1,1,0,0,1,0,0,0,0,0,0,1

%N Triangle read by rows: T(n,m) is the number of integers k such that floor(n/k) = m, n >= 1, k = 1..n.

%C The sum of numbers in row n is n.

%C Number of terms > 0 per row: Sum_{k=1..n} A063524(T(n,k)) = A055086(n). - _Reinhard Zumkeller_, Apr 06 2006

%H Michael De Vlieger, <a href="/A075993/b075993.txt">Table of n, a(n) for n = 1..11325</a> (rows 1 <= n <= 150, flattened)

%F T(n, m) = floor(n/m) - floor(n/(m+1)).

%e T(5, 1) = 3 counts k such that floor(5/k) = 1, namely k = 5, 4, 3.

%e First 10 rows:

%e 1

%e 1 1

%e 2 0 1

%e 2 1 0 1

%e 3 1 0 0 1

%e 3 1 1 0 0 1

%e 4 1 1 0 0 0 1

%e 4 2 0 1 0 0 0 1

%e 5 1 1 1 0 0 0 0 1

%e 5 2 1 0 1 0 0 0 0 1

%t Table[Floor[n/m] - Floor[n/(m + 1)], {n, 14}, {m, n}] // Flatten (* _Michael De Vlieger_, Jan 14 2022 *)

%Y Columns 1, 2, 3 are essentially A004526, A008615, A008679.

%Y Cf. A010766.

%K nonn,tabl

%O 1,4

%A _Clark Kimberling_, Sep 28 2002