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.

A289505 Decimal expansion of arcsec(3)/(2*Pi).

Original entry on oeis.org

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

Views

Author

R. J. Mathar, Jul 07 2017

Keywords

Examples

			0.195913276015303635085427779611215...
		

Crossrefs

Programs

  • Maple
    arcsec(3)/2/Pi ; evalf(%) ;
  • Mathematica
    RealDigits[ArcSec[3]/(2 Pi),10,120][[1]] (* Harvey P. Dale, Jul 21 2021 *)
  • PARI
    acos(1/3)/(2*Pi) \\ Michel Marcus, Jul 07 2017
  • Python
    from mpmath import mp, asec, pi
    mp.dps=89
    print([int(z) for z in list(str(asec(3)/(2*pi))[2:-1])]) # Indranil Ghosh, Jul 07 2017
    

Formula

From Robert FERREOL, Mar 21 2018: (Start)
Equals arctan(2*sqrt(2))/(2*Pi).
Equals (1/(2*Pi))*Integral_{t>=sqrt(2)/4} 1/(1+t^2).
Equals Probability(X>sqrt(2)/4)/2, if X is a Cauchy distributed random variable of location parameter 0 and scale parameter 1.
Equals the asymptotic probability p that A is predominantly preferred to B and B predominantly preferred to C when n persons provide a preference list of three candidates A, B, C (with a uniform distribution on voter preferences); the asymptotic probability that A > B > C > A or A > C > B > A (where ">" means "predominantly preferred to") is 3p-1/2 = 8.77...% (Condorcet paradox); the contrary probability (existence of a Condorcet winner) is 3/2-3p = 91.226...%.
See Gehrlein link. (End)