OFFSET
1,1
LINKS
FORMULA
Equals Pi - arcsin(sqrt(1/3)) = Pi - arctan(sqrt(1/2)). - Amiram Eldar, Jul 10 2023
EXAMPLE
arccos(-sqrt(2/3)) = 2.5261129449405...
MATHEMATICA
r = Sqrt[2/3];
N[ArcSin[r], 100]
RealDigits[%] (* A195696 *)
N[ArcCos[r], 100]
RealDigits[%] (* A195695 *)
N[ArcTan[r], 100]
RealDigits[%] (* A195701 *)
N[ArcCos[-r], 100]
RealDigits[%] (* A195702 *)
RealDigits[ArcCos[-Sqrt[(2/3)]], 10, 120][[1]] (* Harvey P. Dale, Jan 15 2013 *)
PROG
(PARI) acos(-sqrt(2/3)) \\ G. C. Greubel, Nov 18 2017
(Magma) [Arccos(-Sqrt(2/3))]; // G. C. Greubel, Nov 18 2017
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Sep 23 2011
STATUS
approved