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.

A262674 Decimal expansion of the real root of x^3 - 6x^2 + 4x - 2.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Sep 27 2015

Keywords

Comments

Algebraic integer of degree 3. - Charles R Greathouse IV, Apr 18 2016

Examples

			5.318628217750185659109680153318022467721919808836900260228...
		

Crossrefs

Cf. A060295.

Programs

  • Mathematica
    RealDigits[Root[#^3 - 6#^2 + 4# - 2&, 1], 10, 106] // First
  • PARI
    solve(x=5, 6, x^3 - 6*x^2 + 4*x - 2) \\ Michel Marcus, Sep 27 2015
    
  • PARI
    polrootsreal(x^3-6*x^2+4*x-2)[1] \\ Charles R Greathouse IV, Apr 18 2016

Formula

Equals (1/3)*(6 + (135 - 3*sqrt(489))^(1/3) + (3*(45 + sqrt(489)))^(1/3)).
Also equals exp(Pi*i/24)*eta(tau)/eta(2*tau), where eta is Dedekind's eta function and tau = (1 + sqrt(163) i) / 2.
Equals 2 + A160332. - R. J. Mathar, Sep 29 2015