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%I #11 Sep 08 2022 08:46:17
%S 1,2,3,4,1,5,1,6,1,7,1,8,2,9,2,1,10,2,1,11,2,1,12,3,1,13,3,1,14,3,1,
%T 15,3,1,16,4,1,1,17,4,1,1,18,4,2,1,19,4,2,1,20,5,2,1,21,5,2,1,22,5,2,
%U 1,23,5,2,1,24,6,2,1,25,6,2,1,1,26,6,2,1,1,27,6,3,1,1,28,7,3,1,1,29,7,3,1,1
%N Irregular triangle read by rows: T(n,k) = floor(n/k^2) for 1 <= k^2 <= n.
%C The row length sequence is A000196.
%H Jason Kimberley, <a href="/A278108/b278108.txt">Table of n, a(n) for n = 1..20615 (the first 1000 rows of the triangle)</a>
%e The first 27 rows are:
%e 1;
%e 2;
%e 3;
%e 4, 1;
%e 5, 1;
%e 6, 1;
%e 7, 1;
%e 8, 2;
%e 9, 2, 1;
%e 10, 2, 1;
%e 11, 2, 1;
%e 12, 3, 1;
%e 13, 3, 1;
%e 14, 3, 1;
%e 15, 3, 1;
%e 16, 4, 1, 1;
%e 17, 4, 1, 1;
%e 18, 4, 2, 1;
%e 19, 4, 2, 1;
%e 20, 5, 2, 1;
%e 21, 5, 2, 1;
%e 22, 5, 2, 1;
%e 23, 5, 2, 1;
%e 24, 6, 2, 1;
%e 25, 6, 2, 1, 1;
%e 26, 6, 2, 1, 1;
%e 27, 6, 3, 1, 1;
%o (Magma) [n div k^2:k in[1..Isqrt(n)],n in[1..27]];
%Y Cf. A000196, A010766, A277646, A277647, A278109.
%K nonn,easy,tabf
%O 1,2
%A _Jason Kimberley_, Feb 01 2017
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