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A195709
Decimal expansion of arctan(sqrt(2/5)).
3
5, 6, 3, 9, 4, 2, 6, 4, 1, 3, 6, 0, 6, 2, 8, 8, 4, 2, 6, 9, 3, 8, 3, 1, 1, 7, 2, 1, 8, 3, 7, 4, 6, 8, 4, 7, 8, 5, 1, 8, 5, 9, 5, 3, 9, 3, 0, 4, 2, 5, 6, 7, 8, 3, 7, 5, 7, 2, 4, 2, 6, 6, 4, 2, 6, 6, 9, 2, 6, 2, 7, 9, 6, 5, 7, 8, 7, 4, 1, 2, 3, 6, 4, 0, 9, 2, 9, 4, 5, 7, 1, 8, 8, 3, 8, 4, 5, 1, 4, 2
OFFSET
0,1
EXAMPLE
arctan(sqrt(2/5)) = 0.5639426413606...
MATHEMATICA
r = Sqrt[1/5]; s = Sqrt[2/5];
N[ArcSin[r], 100]
RealDigits[%] (* A073000 *)
N[ArcCos[r], 100]
RealDigits[%] (* A105199 *)
N[ArcTan[r], 100]
RealDigits[%] (* A188595 *)
N[ArcCos[-r], 100]
RealDigits[%] (* A137218 *)
N[ArcSin[s], 100]
RealDigits[%] (* A195701 *)
N[ArcCos[s], 100]
RealDigits[%] (* A195708 *)
N[ArcTan[s], 100]
RealDigits[%] (* A195709 *)
N[ArcCos[-s], 100]
RealDigits[%] (* A195710 *)
PROG
(PARI) atan(sqrt(2/5)) \\ G. C. Greubel, Nov 18 2017
(Magma) [Arctan(Sqrt(2/5))]; // G. C. Greubel, Nov 18 2017
CROSSREFS
Cf. A195708.
Sequence in context: A329197 A153614 A328905 * A257837 A099038 A064206
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Sep 23 2011
STATUS
approved