

A195723


Decimal expansion of arctan(golden ratio).


3



1, 0, 1, 7, 2, 2, 1, 9, 6, 7, 8, 9, 7, 8, 5, 1, 3, 6, 7, 7, 2, 2, 7, 8, 8, 9, 6, 1, 5, 5, 0, 4, 8, 2, 9, 2, 2, 0, 6, 3, 5, 6, 0, 8, 7, 6, 9, 8, 6, 8, 3, 6, 5, 8, 7, 1, 4, 9, 2, 0, 2, 6, 9, 2, 4, 3, 7, 0, 5, 3, 0, 3, 3, 6, 5, 4, 4, 2, 3, 1, 0, 2, 3, 0, 7, 3, 0, 8, 8, 4, 8, 3, 2, 7, 9, 7, 3, 2, 1, 3
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OFFSET

1,4


COMMENTS

The polar angle, in radians, of the cone circumscribed to a regular icosahedron from one of its vertices.  Stanislav Sykora, Feb 15 2014


LINKS

Stanislav Sykora, Table of n, a(n) for n = 1..2000


FORMULA

Equals arccos(sqrt((5sqrt(5))/10)).  Stanislav Sykora, Feb 15 2014


EXAMPLE

arctan((1+sqrt(5))/2) = 1.0172219678978513677227...


MATHEMATICA

r=GoldenRatio; N[ArcTan[r], 100]
RealDigits[%] (* A195723 *)


PROG

(PARI) atan((1+sqrt(5))/2) \\ G. C. Greubel, Aug 20 2018
(MAGMA) SetDefaultRealField(RealField(100)); Arctan((1+Sqrt(5))/2); // G. C. Greubel, Aug 20 2018


CROSSREFS

Cf. A001622, A195693, A243445.
Sequence in context: A176704 A289917 A198415 * A138996 A010141 A316247
Adjacent sequences: A195720 A195721 A195722 * A195724 A195725 A195726


KEYWORD

nonn,cons,easy


AUTHOR

Clark Kimberling, Sep 23 2011


STATUS

approved



