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A194373
Numbers m such that Sum_{k=1..m} (<1/2 + k*r> - <k*r>) > 0, where r=sqrt(3) and < > denotes fractional part.
4
3, 7, 11, 29, 33, 37, 41, 43, 44, 45, 47, 48, 49, 51, 52, 53, 55, 59, 63, 67, 85, 89, 93, 97, 99, 100, 101, 103, 104, 105, 107, 108, 109, 111, 115, 119, 123, 141, 145, 149, 153, 155, 156, 157, 159, 160, 161, 163, 164, 165, 167, 171, 175, 179, 197
OFFSET
1,1
COMMENTS
See A194368.
LINKS
MATHEMATICA
r = Sqrt[3]; 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, 100}];
Flatten[Position[t1, 1]] (* A194371 *)
t2 = Table[If[y[n] == x[n], 1, 0], {n, 1, 800}];
Flatten[Position[t2, 1]] (* A194372 *)
t3 = Table[If[y[n] > x[n], 1, 0], {n, 1, 100}];
Flatten[Position[t3, 1]] (* A194373 *)
PROG
(PARI) isok(n) = sum(k=1, n, frac(1/2+k*sqrt(3)) - frac(k*sqrt(3))) > 0; \\ Michel Marcus, Sep 10 2018
CROSSREFS
Sequence in context: A066674 A125878 A126112 * A156210 A343718 A264803
KEYWORD
nonn
AUTHOR
Clark Kimberling, Aug 23 2011
STATUS
approved