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Number of k in [1,n] for which <n*r>+<k*r> > 1, where < > = fractional part and r = (1+sqrt(5))/2 (the golden ratio); row sums of A164661.
2

%I #5 Mar 30 2012 18:57:43

%S 1,0,3,2,0,4,2,8,6,2,9,5,0,9,3,14,9,2,14,7,21,14,5,21,12,2,19,8,27,17,

%T 5,25,13,0,22,8,32,18,3,28,13,40,25,8,37,20,2,32,13,45,27,7,40,20,55,

%U 35,13,50,28,5,43,20,60,37,12,53,28,2,45,18,63,36,8,54,26,74,46

%N Number of k in [1,n] for which <n*r>+<k*r> > 1, where < > = fractional part and r = (1+sqrt(5))/2 (the golden ratio); row sums of A164661.

%t r = GoldenRatio; z = 14;

%t p[x_] := FractionalPart[x]; f[x_] := Floor[x];

%t h[n_, k_] := f[p[n*r] + p[k*r]]

%t Flatten[Table[h[n, k], {n, 1, z}, {k, 1, n}]] (* A194661 *)

%t TableForm[Table[h[n, k], {n, 1, z}, {k, 1, n}]]

%t t[n_] := Sum[h[n, k], {k, 1, n}]

%t Table[t[n], {n, 1, 100}] (* A194662 *)

%Y Cf. A194661.

%K nonn

%O 1,3

%A _Clark Kimberling_, Sep 01 2011