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A194387
Numbers m such that Sum_{k=1..m} (<1/2 + k*r> - <k*r>) < 0, where r=sqrt(11) and < > denotes fractional part.
4
3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 25, 27, 28, 29, 31, 47, 49, 50, 51, 53, 63, 65, 66, 67, 68, 69, 70, 71, 72, 73, 75, 85, 87, 88, 89, 91, 107, 109, 110, 111, 113, 123, 125, 126, 127, 128, 129, 130, 131, 132, 133, 135, 145, 147, 148, 149, 151, 167, 169, 170
OFFSET
1,1
COMMENTS
See A194368.
MATHEMATICA
r = Sqrt[11]; c = 1/2;
x[n_] := Sum[FractionalPart[k*r], {k, 1, n}]
y[n_] := Sum[FractionalPart[c + k*r], {k, 1, n}]
t1 = Table[If[y[n] < x[n], 1, 0], {n, 1, 200}];
Flatten[Position[t1, 1]] (* A194387 *)
t2 = Table[If[y[n] == x[n], 1, 0], {n, 1, 200}];
Flatten[Position[t2, 1]] (* A194388 *)
t3 = Table[If[y[n] > x[n], 1, 0], {n, 1, 200}];
Flatten[Position[t3, 1]] (* A194389 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Aug 23 2011
STATUS
approved