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.

A280725 Decimal expansion of 22*sin(Pi/22).

Original entry on oeis.org

3, 1, 3, 0, 9, 2, 6, 4, 4, 2, 0, 1, 2, 2, 7, 3, 0, 8, 9, 7, 6, 3, 4, 3, 8, 7, 0, 9, 5, 6, 0, 1, 3, 2, 7, 1, 3, 4, 0, 3, 1, 2, 9, 9, 4, 4, 7, 7, 1, 6, 5, 5, 2, 2, 5, 1, 9, 7, 8, 2, 1, 3, 0, 4, 2, 9, 8, 1, 2, 0, 7, 7, 1, 2, 1, 9, 2, 2, 1, 4, 8, 5, 8, 3, 9, 2, 1, 4, 7, 1, 6, 7, 2, 0, 7, 9, 7, 6, 1, 7, 0, 3, 6, 3, 3
Offset: 1

Views

Author

Rick L. Shepherd, Jan 07 2017

Keywords

Comments

The ratio of the perimeter of a regular 11-gon (hendecagon) to its diameter (largest diagonal).
Also least positive root of x^5 - 11x^4 - 484x^3 + 3993x^2 + 43923x - 161051.

Examples

			3.130926442012273089763438709560132713403129944771655225197821304298120771...
		

Crossrefs

Cf. For other n-gons: A010466 (n=4), 10*A019827 (n=5, 10), A280533 (n=7), A280585 (n=8), A280633 (n=9), A280819 (n=12).

Programs

  • Maple
    evalf(22*sin(Pi/22),100); # Wesley Ivan Hurt, Feb 01 2017
  • Mathematica
    RealDigits[22*Sin[Pi/22], 10, 120][[1]] (* Amiram Eldar, Jun 26 2023 *)
  • PARI
    22*sin(Pi/22)