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Triangular array: g(n,k)=number of fractional parts (i*sqrt(5)) in interval [(k-1)/n, k/n], for 1<=i<=n^2, 1<=k<=n.
2

%I #5 Mar 30 2012 18:57:42

%S 1,2,2,3,3,3,4,4,4,4,5,4,6,5,5,6,7,7,6,5,5,7,7,7,8,7,6,7,8,9,7,9,7,9,

%T 7,8,8,10,9,9,9,9,9,9,9,9,11,9,10,12,9,10,10,10,10,10,12,11,11,11,11,

%U 12,11,10,11,11,12,12,12,12,12,12,12,12,12,12,12,12,12,13,13,14

%N Triangular array: g(n,k)=number of fractional parts (i*sqrt(5)) in interval [(k-1)/n, k/n], for 1<=i<=n^2, 1<=k<=n.

%C See A194285.

%e First eight rows:

%e 1

%e 2..2

%e 3..3..3

%e 4..4..4..4

%e 5..4..6..5..5

%e 6..7..7..6..5..5

%e 7..7..7..8..7..6..7

%e 8..9..7..9..7..9..7..8

%t r = Sqrt[5];

%t f[n_, k_, i_] := If[(k - 1)/n <= FractionalPart[i*r] < k/n, 1, 0]

%t g[n_, k_] := Sum[f[n, k, i], {i, 1, n^2}]

%t TableForm[Table[g[n, k], {n, 1, 14}, {k, 1, n}]]

%t Flatten[%] (* A194303 *)

%Y Cf. A194285.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Aug 21 2011