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 1-2 of 2 results.

A094884 Decimal expansion of phi/sqrt(2), where phi = (1+sqrt(5))/2.

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Jun 15 2004

Keywords

Comments

An algebraic number with minimal polynomial 4*x^4 - 6*x^2 + 1. - Charles R Greathouse IV, Mar 25 2014

Examples

			1.144122805635368595200145567160604153072306753675541225...

Links

Crossrefs

Cf. A001622 (phi), A002193 (sqrt(2)), A017329, A094887, A239798.

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); (1+Sqrt(5) )/(2*Sqrt(2)); // G. C. Greubel, Sep 27 2018
  • Mathematica
    RealDigits[GoldenRatio/Sqrt[2],10,120][[1]] (* Harvey P. Dale, Feb 11 2015 *)
  • PARI
    sqrt(sqrt(5)+3)/2 \\ Charles R Greathouse IV, Mar 25 2014

Formula

Equals Product_{k>=0} (1 + (-1)^k/(10*k+5)). - Amiram Eldar, Nov 23 2024
Equals A094887/2 = sqrt(A239798). - Hugo Pfoertner, Nov 23 2024

A370944 Decimal expansion of ((1+sqrt(5))/2)*sqrt(3) = A001622*A002194.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Mar 07 2024

Keywords

Comments

Long space diagonal of a regular dodecahedron with unit edges.

Examples

			2.80251707688814708935335587064413598888786347955...

Links

Crossrefs

Cf. A001622, A002194.
Cf. A094887 (short diagonal), A104457 (medium diagonal).

Programs

  • Maple
    (sqrt(3) + sqrt(15))/2: evalf(%, 86);  # Peter Luschny, Mar 07 2024
  • Mathematica
    First[RealDigits[GoldenRatio*Sqrt[3], 10, 100]]

Formula

Equals 2*A179296. - Hugo Pfoertner, Mar 07 2024
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.