OFFSET
0,2
FORMULA
Equals sqrt( (2-sqrt(2+sqrt(2)))/(2+sqrt(2+sqrt(2))) ).
Equals sqrt(4+2*sqrt(2))-sqrt(2)-1.
EXAMPLE
0.19891236737965800691159762264...
MATHEMATICA
RealDigits[Tan[Pi/16], 10, 100][[1]] (* Amiram Eldar, Apr 27 2021 *)
PROG
(PARI) tan(Pi/16)
(PARI) sqrt((2-sqrt(2+sqrt(2)))/(2+sqrt(2+sqrt(2))))
(PARI) sqrt(4+2*sqrt(2))-sqrt(2)-1
CROSSREFS
KEYWORD
AUTHOR
Seiichi Manyama, Apr 04 2021
STATUS
approved