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.

A275615 Decimal expansion of 22/111.

Original entry on oeis.org

1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8, 1, 9, 8
Offset: 0

Views

Author

Peter M. Chema, Aug 03 2016

Keywords

Comments

Period 3: repeat [1,9,8]. Also the digital root of Nexus numbers A022522.
Other variants of this period are decimal expansions of 91/111 (.819 repeating) and 109/111 (.981 repeating).

Examples

			0.198198198198198198198198198198198198198198198198198198198...
		

Crossrefs

Programs

  • Mathematica
    First@ RealDigits@ N[22/111, 120] (* or *)
    PadRight[{}, 120, {1, 9, 8}] (* or *)
    FixedPoint[Total@ IntegerDigits@ # &, #] & /@ Table[(n + 1)^6 - n^6, {n, 0, 120}] (* Michael De Vlieger, Aug 04 2016 *)
  • PARI
    a(n) = my(x=[1, 9, 8]); x[n%3+1] \\ Felix Fröhlich, Aug 04 2016

Formula

a(n) = A010888(A022522(n)).
a(n) = 6 - 5*cos(2*n*Pi/3) + sin(2*n*Pi/3)/sqrt(3). - Wesley Ivan Hurt, Oct 04 2018