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.

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

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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...
		

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