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.

Showing 1-3 of 3 results.

A189088 Decimal expansion of Pi - sqrt(Pi^2 - 1).

Original entry on oeis.org

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

Views

Author

Clark Kimberling, Apr 16 2011

Keywords

Comments

Decimal expansion of the shape (= length/width = Pi - sqrt(-1+Pi^2)) of the lesser 2*Pi-contraction rectangle.
See A188738 for an introduction to lesser and greater r-contraction rectangles, their shapes, and partitioning these rectangles into a sets of squares in a manner that matches the continued fractions of their shapes.

Examples

			0.1634045465204364424868140709760745094117386882...
		

Crossrefs

Programs

  • Mathematica
    r = 2*Pi; t = (r - (-4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]]  (* A189088 *)
    ContinuedFraction[t, 120]
    RealDigits[Pi-Sqrt[Pi^2-1],10,150][[1]] (* Harvey P. Dale, Sep 25 2016 *)
  • PARI
    Pi*(1-sqrt(1-1/Pi^2)) \\ Charles R Greathouse IV, May 07 2011

A189090 Continued fraction of Pi + sqrt(Pi^2 - 1).

Original entry on oeis.org

6, 8, 2, 1, 6, 1, 1, 1, 1, 1, 1, 1, 1, 2, 6, 1, 14, 2, 1, 6, 3, 1, 1, 2, 3, 7, 1, 1, 3, 2, 2, 1, 3, 10, 1, 1, 4, 3, 3, 10, 1, 2, 2, 18, 3, 77, 1, 1, 18, 1, 2, 2, 4, 1, 2, 8, 1, 4, 1, 44, 1, 28, 1, 4, 1, 1, 2, 116, 1, 1, 2, 2, 1, 5, 4, 5, 27, 4, 1, 3, 1, 3, 5, 1, 2, 2, 1, 16, 1, 3, 1, 5, 2, 1, 1, 25, 3, 1, 1, 17, 1, 5, 3, 1, 2, 1, 4, 12, 4, 7, 42, 19, 1, 2, 23, 1, 3, 2, 1, 4
Offset: 0

Views

Author

Clark Kimberling, Apr 16 2011

Keywords

Crossrefs

Programs

  • Mathematica
    r = 2*Pi; t = (r + (-4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]] (*A189089*)
    ContinuedFraction[t, 120]  (*A189090*)
  • PARI
    contfrac(Pi+sqrt(Pi^2-1)) \\ Charles R Greathouse IV, Jul 29 2011

A359540 Decimal expansion of arccosh(Pi).

Original entry on oeis.org

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

Views

Author

Wolfe Padawer, Jan 05 2023

Keywords

Examples

			1.811526272460853107021852049305420510220702081057922474861595622974...
		

References

  • Jerome Spanier and Keith B. Oldham, "Atlas of Functions", Hemisphere Publishing Corp., 1987, chapter 31, page 291.

Crossrefs

Cf. A189089.

Programs

  • Mathematica
    RealDigits[Abs[ArcCos[Pi]], 10, 105][[1]]
  • PARI
    -I*acos(Pi) \\ Hugo Pfoertner, Jan 24 2023

Formula

Equals |arccos(Pi)|.
Equals log(Pi + sqrt(Pi^2 - 1)) = log(A189089). - Amiram Eldar, Jan 05 2023
Showing 1-3 of 3 results.