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!)
A054072 Position of n in the permutation of 1,2,...,n obtained by ordering the fractional parts {h*sqrt(2)} for h=1,2,...,n. 4
1, 2, 1, 3, 1, 4, 7, 3, 7, 2, 7, 12, 5, 11, 3, 10, 1, 9, 17, 6, 15, 3, 13, 23, 9, 20, 5, 17, 1, 14, 27, 9, 23, 4, 19, 34, 13, 29, 7, 24, 41, 17, 35, 10, 29, 3, 23, 43, 15, 36, 7, 29, 51, 20, 43, 11, 35, 2, 27, 52, 17, 43, 7, 34, 61, 23, 51, 12, 41 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..5000

MATHEMATICA

r = Sqrt[2]; p[x_] := FractionalPart[x];

u[n_, k_] := If[p[k*r] <= p[n*r], 1, 0]

v[n_, k_] := If[p[k*r] > p[n*r], 1, 0]

s[n_] := Sum[u[n, k], {k, 1, n}]

t[n_] := Sum[v[n, k], {k, 1, n}]

Table[s[n], {n, 1, 100}]   (* this sequence *)

Table[t[n], {n, 1, 100}]   (* A194735 *)

CROSSREFS

Cf. A194735, A194738, A019587.

Sequence in context: A034868 A050382 A197956 * A325642 A110977 A295785

Adjacent sequences:  A054069 A054070 A054071 * A054073 A054074 A054075

KEYWORD

nonn

AUTHOR

Clark Kimberling

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 July 14 16:21 EDT 2020. Contains 335729 sequences. (Running on oeis4.)