OFFSET
0,1
COMMENTS
LINKS
Stanislav Sykora, Table of n, a(n) for n = 0..2000
Wikipedia, Constructible number
Wikipedia, Regular polygon
FORMULA
Equals 2*sin(Pi/11) = 2*cos(Pi*9/22).
EXAMPLE
0.5634651136828593954228358306932337980715557979465337436621606121...
MATHEMATICA
RealDigits[N[2Sin[Pi/11], 100]][[1]] (* Robert Price, May 01 2016 *)
PROG
(PARI) 2*sin(Pi/11)
CROSSREFS
KEYWORD
AUTHOR
Stanislav Sykora, May 01 2016
STATUS
approved