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.

A354222 Decimal expansion of 2 / (Pi+2).

Original entry on oeis.org

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

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Author

Bernard Schott, May 19 2022

Keywords

Comments

The sequence u(n+1) = 1 / ( u(n) + 1/(n+1) ) with u(0) >= 0 is convergent with lim_{n->oo} u(n) = 1; however, this sequence is monotonic iff u(0) = 2 / (Pi+2), and in this case, this sequence is increasing.

Examples

			0.388984529648342710619404612046031138262577367...
		

References

  • J. M. Arnaudiès, P. Delezoide et H. Fraysse, Exercices résolus d'Analyse du cours de mathématiques - 2, Dunod, 1993, Exercice 1, pp. 29-35.

Crossrefs

Programs

  • Maple
    evalf(2/(Pi+2), 100);
  • Mathematica
    RealDigits[2/(Pi + 2), 10, 100][[1]] (* Amiram Eldar, May 19 2022 *)
  • PARI
    2/(Pi+2) \\ Michel Marcus, May 20 2022

Formula

Equals 1 - A197686.