%I #15 Jul 08 2023 04:02:04
%S 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,
%T 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,
%U 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
%N Decimal expansion of arctan(sqrt(5/8)).
%H G. C. Greubel, <a href="/A195707/b195707.txt">Table of n, a(n) for n = 0..10000</a>
%F Equals arcsin(sqrt(5/13)) = arccos(2*sqrt(2/13)). - _Amiram Eldar_, Jul 08 2023
%e arctan(sqrt(5/8)) = 0.6689640742...
%t r = Sqrt[5/8];
%t N[ArcSin[r], 100]
%t RealDigits[%] (* A195703 *)
%t N[ArcCos[r], 100]
%t RealDigits[%] (* A195700 *)
%t N[ArcTan[r], 100]
%t RealDigits[%] (* A195707 *)
%t N[ArcCos[-r], 100]
%t RealDigits[%] (* A195711 *)
%o (PARI) atan(sqrt(5/8)) \\ _G. C. Greubel_, Aug 19 2018
%o (Magma) SetDefaultRealField(RealField(100)); Arctan(Sqrt(5/8)); // _G. C. Greubel_, Aug 19 2018
%Y Cf. A195700, A195703, A195711.
%K nonn,cons
%O 0,1
%A _Clark Kimberling_, Sep 23 2011
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