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.

A189089 Decimal expansion of Pi + sqrt(-1 + Pi^2).

Original entry on oeis.org

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

Views

Author

Clark Kimberling, Apr 16 2011

Keywords

Comments

Decimal expansion of the shape (= length/width = Pi + sqrt(-1 + Pi^2)) of the greater 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

			6.119780760659150034438472695582931258982600110...
		

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*)
    RealDigits[Pi+Sqrt[Pi^2-1],10,150][[1]] (* Harvey P. Dale, Apr 18 2025 *)
  • PARI
    Pi + sqrt(Pi^2-1) \\ Charles R Greathouse IV, Oct 02 2022