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Numbers m such that Sum_{k=1..m} (<c + k*r> - <k*r>) < 0, where r=(1+sqrt(5))/2 and c=(-1+sqrt(5))/4, and < > denotes fractional part.
1

%I #11 Feb 14 2021 21:53:39

%S 3,6,8,9,11,12,16,19,21,22,24,25,29,32,42,45,55,58,61,63,64,66,67,71,

%T 74,76,77,79,80,84,87,97,100,110,113,116,118,119,121,122,126,129,131,

%U 132,134,135,139,142,144,145,147,148,150,151,152,153,154,155,156

%N Numbers m such that Sum_{k=1..m} (<c + k*r> - <k*r>) < 0, where r=(1+sqrt(5))/2 and c=(-1+sqrt(5))/4, and < > denotes fractional part.

%C See A194368.

%t r = GoldenRatio; c = (1/2) FractionalPart[r];

%t x[n_] := Sum[FractionalPart[k*r], {k, 1, n}]

%t y[n_] := Sum[FractionalPart[c + k*r], {k, 1, n}]

%t t1 = Table[If[y[n] < x[n], 1, 0], {n, 1, 200}];

%t Flatten[Position[t1, 1]] (* A184461 *)

%t t3 = Table[If[y[n] > x[n], 1, 0], {n, 1, 200}];

%t Flatten[Position[t3, 1]] (* A184462 *)

%Y Cf. A194368.

%K nonn

%O 1,1

%A _Clark Kimberling_, Aug 24 2011