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A195707
Decimal expansion of arctan(sqrt(5/8)).
2
6, 6, 8, 9, 6, 4, 0, 7, 4, 2, 6, 8, 4, 0, 7, 1, 3, 0, 1, 4, 1, 3, 2, 7, 1, 1, 2, 6, 1, 2, 1, 7, 6, 4, 7, 8, 0, 1, 6, 9, 3, 0, 7, 1, 8, 1, 1, 9, 6, 3, 4, 7, 0, 8, 1, 6, 2, 9, 2, 9, 7, 6, 0, 3, 5, 2, 0, 5, 0, 4, 1, 5, 4, 9, 0, 1, 8, 2, 2, 3, 8, 8, 0, 5, 9, 8, 6, 4, 2, 4, 0, 2, 1, 7, 7, 4, 0, 4, 3, 1
OFFSET
0,1
FORMULA
Equals arcsin(sqrt(5/13)) = arccos(2*sqrt(2/13)). - Amiram Eldar, Jul 08 2023
EXAMPLE
arctan(sqrt(5/8)) = 0.6689640742...
MATHEMATICA
r = Sqrt[5/8];
N[ArcSin[r], 100]
RealDigits[%] (* A195703 *)
N[ArcCos[r], 100]
RealDigits[%] (* A195700 *)
N[ArcTan[r], 100]
RealDigits[%] (* A195707 *)
N[ArcCos[-r], 100]
RealDigits[%] (* A195711 *)
PROG
(PARI) atan(sqrt(5/8)) \\ G. C. Greubel, Aug 19 2018
(Magma) SetDefaultRealField(RealField(100)); Arctan(Sqrt(5/8)); // G. C. Greubel, Aug 19 2018
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Sep 23 2011
STATUS
approved