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%I #32 Aug 21 2023 12:37:55
%S 1,4,0,1,2,5,8,5,3,8,4,4,4,0,7,3,5,4,4,6,7,6,6,7,7,9,3,5,3,2,2,0,6,7,
%T 9,9,4,4,4,3,9,3,1,7,3,9,7,7,5,4,9,2,8,6,3,6,6,0,8,4,5,1,8,6,3,9,1,3,
%U 5,4,0,2,7,2,1,1,4,4,4,7,6,7,6,5,0,1,0,8,3,9,0,9,0,3,9,8,0,5,2,3,3,9,7,9,8
%N Decimal expansion of circumradius of a regular dodecahedron with edge length 1.
%C Dodecahedron: A three-dimensional figure with 12 faces, 20 vertices, and 30 edges.
%C Appears as a coordinate in a degree-7 quadrature formula on 12 points over the unit circle [Stroud & Secrest]. - _R. J. Mathar_, Oct 12 2011
%H Chai Wah Wu, <a href="/A179296/b179296.txt">Table of n, a(n) for n = 1..10001</a>
%H A. H. Stroud and Don Secrest, <a href="http://dx.doi.org/10.1090/S0025-5718-1963-0161473-0">Approximate integration formulas for certain spherically symmetric regions</a>, Math. Comp. 17 (82) (1963) 105.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Dodecahedron">Dodecahedron</a>.
%H Wolfram Alpha, <a href="http://www.wolframalpha.com/input/?i=Dodecahedron">Dodecahedron</a>.
%H <a href="/index/Al#algebraic_04">Index entries for algebraic numbers, degree 4</a>
%F Equals (sqrt(3) + sqrt(15))/4 = sqrt((9 + 3*sqrt(5))/8).
%F The minimal polynomial is 16*x^4 - 36*x^2 + 9. - _Joerg Arndt_, Feb 05 2014
%F Equals (sqrt(3)/2) * phi = A010527 * A001622. - _Amiram Eldar_, Jun 02 2023
%e 1.40125853844407354467667793532206799444393173977549286366084518639135...
%t RealDigits[N[(Sqrt[3]+Sqrt[15])/4,175]]
%Y Cf. A001622, A102208, A102769, A131595, A179290, A179292, A179294.
%Y Cf. Platonic solids circumradii: A010503 (octahedron), A010527 (cube), A019881 (icosahedron), A187110 (tetrahedron). - _Stanislav Sykora_, Feb 10 2014
%K nonn,cons,easy
%O 1,2
%A _Vladimir Joseph Stephan Orlovsky_, Jul 09 2010
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