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!)
A194380 Numbers n such that sum{<1/2+k*r>-<k*r> : 1<=k<=n}>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.

Sequence in context: A280647 A152045 A041479 * A269267 A025358 A095473

Adjacent sequences:  A194377 A194378 A194379 * A194381 A194382 A194383

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 January 28 09:52 EST 2020. Contains 331319 sequences. (Running on oeis4.)