cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A038130 Beatty sequence for 2*Pi.

Original entry on oeis.org

0, 6, 12, 18, 25, 31, 37, 43, 50, 56, 62, 69, 75, 81, 87, 94, 100, 106, 113, 119, 125, 131, 138, 144, 150, 157, 163, 169, 175, 182, 188, 194, 201, 207, 213, 219, 226, 232, 238, 245, 251, 257, 263, 270, 276, 282, 289, 295, 301, 307, 314, 320, 326, 333, 339, 345
Offset: 0

Views

Author

Keywords

Comments

a(n) = floor[circumference of a circle of radius n]. - Mohammad K. Azarian, Feb 29 2008
This sequence consists of the nonnegative integers k satisfying sin(k) <= 0 and sin(k+1) >= 0; thus this sequence and A246388 partition A022844 (the Beatty sequence for Pi). - Clark Kimberling, Aug 24 2014

Crossrefs

Complement of A108586.
For ceiling (2*Pi*n) see A004082.

Programs

  • Mathematica
    Table[Floor[2 n*Pi], {n, 0, 100}] (* or *)
    Select[Range[0, 628], Sin[#] <= 0 && Sin[# + 1] >= 0 &] (* Clark Kimberling, Aug 24 2014 *)

Formula

a(n) = floor(2*Pi*n).
a(n) = A004082(n+1) - 1. - John W. Nicholson, Mar 20 2025

Extensions

More terms from Mohammad K. Azarian, Feb 29 2008