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A194380 Numbers m such that Sum_{k=1..m} (<1/2 + k*r> - <k*r>) > 0, where r=sqrt(7) and < > denotes fractional part. 4
31, 33, 45, 47, 79, 81, 93, 95, 127, 129, 141, 143, 175, 177, 189, 191, 223, 225, 237, 239, 525, 527, 539, 541, 573, 575, 587, 589, 621, 623, 635, 637, 669, 671, 683, 685, 717, 719, 731, 733 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A194368.

LINKS

Table of n, a(n) for n=1..40.

MATHEMATICA

r = Sqrt[7]; 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]]   (* A194378 *)

t2 = Table[If[y[n] == x[n], 1, 0], {n, 1, 300}];

Flatten[Position[t2, 1]]  (* A194379 *)

t3 = Table[If[y[n] > x[n], 1, 0], {n, 1, 800}];

Flatten[Position[t3, 1]]   (* A194380 *)

CROSSREFS

Cf. A194368, A194378, A194379.

Sequence in context: A280647 A152045 A041479 * A269267 A025358 A345480

Adjacent sequences:  A194377 A194378 A194379 * A194381 A194382 A194383

KEYWORD

nonn

AUTHOR

Clark Kimberling, Aug 23 2011

STATUS

approved

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Last modified November 26 21:07 EST 2021. Contains 349344 sequences. (Running on oeis4.)