login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A194371 Numbers n such that Sum_{k=1..n} (<1/2 + k*r> - <k*r>) < 0, where r=sqrt(3) and fractional part is denoted by < >. 4
1, 5, 9, 13, 15, 16, 17, 19, 20, 21, 23, 24, 25, 27, 31, 35, 39, 57, 61, 65, 69, 71, 72, 73, 75, 76, 77, 79, 80, 81, 83, 87, 91, 95, 113, 117, 121, 125, 127, 128, 129, 131, 132, 133, 135, 136, 137, 139, 143, 147, 151, 169, 173, 177, 181, 183, 184, 185, 187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

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.

Sequence in context: A165971 A160522 A314651 * A314652 A062976 A314653

Adjacent sequences:  A194368 A194369 A194370 * A194372 A194373 A194374

KEYWORD

nonn

AUTHOR

Clark Kimberling, Aug 23 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 31 12:42 EDT 2020. Contains 334748 sequences. (Running on oeis4.)