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A194392
Numbers m such that Sum_{k=1..m} (<1/2 + k*r> - <k*r>) < 0, where r=sqrt(13) and < > denotes fractional part.
4
1, 3, 29, 31, 33, 34, 35, 36, 37, 39, 41, 67, 69, 71, 72, 73, 74, 75, 77, 79, 105, 107, 143, 145, 181, 183, 209, 211, 213, 214, 215, 216, 217, 219, 221, 247, 249, 251, 252, 253, 254, 255, 257, 259, 285, 287, 323, 325, 361, 363, 389, 391, 393, 394, 395
OFFSET
1,2
COMMENTS
See A194368.
MATHEMATICA
r = Sqrt[13]; 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, 400}];
Flatten[Position[t1, 1]] (* A194392 *)
t2 = Table[If[y[n] == x[n], 1, 0], {n, 1, 300}];
Flatten[Position[t2, 1]] (* A194393 *)
t3 = Table[If[y[n] > x[n], 1, 0], {n, 1, 100}];
Flatten[Position[t3, 1]] (* A194394 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Aug 23 2011
STATUS
approved