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%I #8 Dec 08 2024 02:48:13
%S 2,7,0,6,6,9,4,6,4,5,4,7,9,2,2,8,7,8,5,6,2,5,8,6,4,4,3,8,3,0,6,8,2,8,
%T 0,4,5,6,9,8,4,4,5,4,5,5,5,7,1,7,1,3,1,9,1,2,4,4,6,3,9,9,4,2,6,1,1,6,
%U 0,6,9,9,3,3,2,9,9,0,5,8,4,7,8,6,4,1,0,1,8,3
%N Decimal expansion of the dihedral angle, in radians, between any two adjacent faces in a disdyakis dodecahedron.
%C The disdyakis dodecahedron is the dual polyhedron of the truncated cuboctahedron (great rhombicuboctahedron).
%H Paolo Xausa, <a href="/A378715/b378715.txt">Table of n, a(n) for n = 1..10000</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Disdyakis_dodecahedron">Disdyakis dodecahedron</a>.
%F Equals arccos(-(71 + 12*sqrt(2))/97) = arccos(-(71 + 12*A002193)/97).
%e 2.7066946454792287856258644383068280456984454555717...
%t First[RealDigits[ArcCos[-(71 + 12*Sqrt[2])/97], 10, 100]] (* or *)
%t First[RealDigits[First[PolyhedronData["DisdyakisDodecahedron", "DihedralAngles"]], 10, 100]]
%Y Cf. A378712 (surface area), A378713 (volume), A378714 (inradius), A378393 (midradius).
%Y Cf. A177870, A195698 and A195702 (dihedral angles of a truncated cuboctahedron (great rhombicuboctahedron)).
%Y Cf. A002193.
%K nonn,cons,easy,new
%O 1,1
%A _Paolo Xausa_, Dec 07 2024