OFFSET
0,1
COMMENTS
Also sin(Pi/8) or sine of 22.5 degrees.
The real part of i^(1/4) or cos(Pi/8) is A144981.
A quartic number of denominator 2 and minimal polynomial 8*x^4 - 8*x^2 + 1. - Charles R Greathouse IV, Jan 09 2022
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..10000
Michael Penn, The exact value of sin 5⅝°??, YouTube video, 2021.
FORMULA
Equals sqrt(2-sqrt(2)) / 2. - Bernard Schott, Apr 12 2022
EXAMPLE
0.382683432365089771728459984...
MAPLE
evalf(sin(Pi/8)) ; # R. J. Mathar, Jan 10 2013
MATHEMATICA
RealDigits[Sqrt[2-Sqrt[2]]/2, 10, 120][[1]] (* G. C. Greubel, Sep 04 2022 *)
PROG
(PARI) sin(Pi/8) \\ Charles R Greathouse IV, Jan 09 2022
(SageMath) numerical_approx(sqrt(2-sqrt(2))/2, digits=120) # G. C. Greubel, Sep 04 2022
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Stanislav Sykora, May 16 2012
STATUS
approved