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.

A098459 Decimal expansion of G/2 + (1/8)*Pi*log(2), where G is Catalan's constant (often also denoted K).

Original entry on oeis.org

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

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Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Sep 08 2004

Keywords

Examples

			0.7301810583765597738398878697...
		

References

  • Jonathan Borwein, David Bailey and Roland Girgensohn, Experimentation in Mathematics: Computational Paths to Discovery, A K Peters, 2004, p. 20.

Crossrefs

Programs

  • Mathematica
    RealDigits[Catalan/2 + Pi*Log[2]/8, 10 , 100][[1]] (* Amiram Eldar, Aug 17 2020 *)

Formula

Equals Integral_{x=0..1} arctan(x) / (x*(x^2+1)) dx.
From Amiram Eldar, Aug 17 2020: (Start)
Equals (1/2) * A006752 + A102886.
Equals Integral_{x=0..Pi/4} x*cot(x) dx. (End)