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.

A188941 Decimal expansion of (9+sqrt(65))/4.

Original entry on oeis.org

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

Views

Author

Clark Kimberling, Apr 14 2011

Keywords

Comments

Apart from the first digit, the same as A171417. Apart from the first 2 digits, the same as A188734. - R. J. Mathar, Apr 15 2011
Decimal expansion of the shape (= length/width = (9+sqrt(65))/4) of the greater (9/2)-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

			4.2655644370746374130916533075759427827835990...
		

Crossrefs

Programs

  • Mathematica
    r = 9/2; t = (r + (-4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]]
    RealDigits[(9+Sqrt[65])/4,10,150][[1]] (* Harvey P. Dale, Jan 31 2023 *)
  • PARI
    (9+sqrt(65))/4 \\ Jinyuan Wang, Apr 14 2020