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%I #20 Sep 08 2022 08:46:17
%S 1,2,1,1,1,3,2,1,1,1,1,1,1,1,4,2,2,2,1,1,1,1,1,1,1,1,1,1,1,1,5,3,2,2,
%T 2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,6,4,3,3,2,2,2,2,2,1,1,1,1,
%U 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,7,4,4,3,3,2,2,2,2,2,2,2
%N Triangle T(n,k) = floor(n/sqrt(k)) for 1 <= k <= n^2, read by rows.
%H Jason Kimberley, <a href="/A277647/b277647.txt">Table of n, a(n) for n = 1..10416 (the first 31 rows of the triangle)</a>
%F T(n,k) = A000196(A277646(n,k)).
%F T(n,k)sqrt(k) <= n < (T(n,k)+1)sqrt(k).
%e The first five rows of the triangle are:
%e 1;
%e 2, 1, 1, 1;
%e 3, 2, 1, 1, 1, 1, 1, 1, 1;
%e 4, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1;
%e 5, 3, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1;
%t Table[Floor[n/Sqrt@ k], {n, 7}, {k, n^2}] // Flatten (* _Michael De Vlieger_, Nov 24 2016 *)
%o (Magma)
%o A277647:=func<n,k|Isqrt(n^2 div k)>;
%o [A277647(n,k):k in[1..n^2],n in[1..7]];
%o (PARI) row(n) = for(k=1, n^2, print1(floor(n/sqrt(k)), ", ")); print("")
%o trianglerows(n) = for(k=1, n, row(k))
%o /* Print initial five rows of triangle as follows: */
%o trianglerows(5) \\ _Felix Fröhlich_, Nov 12 2016
%Y Cf. A010766, A277646, A277648.
%Y The 1000th row is A033432.
%K nonn,tabf,easy
%O 1,2
%A _Jason Kimberley_, Nov 09 2016
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