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A194372 Numbers n such that Sum_{k=1..n} (<1/2 + k*r> - <k*r>) = 0, where r=sqrt(3) and < > denotes fractional part. 4
2, 4, 6, 8, 10, 12, 14, 18, 22, 26, 28, 30, 32, 34, 36, 38, 40, 42, 46, 50, 54, 56, 58, 60, 62, 64, 66, 68, 70, 74, 78, 82, 84, 86, 88, 90, 92, 94, 96, 98, 102, 106, 110, 112, 114, 116, 118, 120, 122, 124, 126, 130, 134, 138, 140, 142, 144, 146, 148, 150, 152 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A194368.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

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 *)

CROSSREFS

Cf. A194368, A194371.

Sequence in context: A238264 A098807 A189562 * A058218 A264986 A140955

Adjacent sequences:  A194369 A194370 A194371 * A194373 A194374 A194375

KEYWORD

nonn

AUTHOR

Clark Kimberling, Aug 23 2011

STATUS

approved

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Last modified December 15 04:23 EST 2019. Contains 329991 sequences. (Running on oeis4.)