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%I #7 Nov 08 2024 11:38:25
%S 3,8,0,2,3,9,4,4,9,9,8,5,1,2,9,3,5,8,4,7,6,6,8,3,6,7,1,4,1,1,0,3,2,3,
%T 2,0,9,3,0,3,8,9,2,8,6,5,2,5,1,2,8,5,6,2,1,1,8,9,2,8,4,3,9,8,2,3,4,3,
%U 9,6,1,4,2,2,8,9,2,1,2,6,6,5,7,3,7,7,7,8,2,4
%N Decimal expansion of the circumradius of a truncated icosidodecahedron (great rhombicosidodecahedron) with unit edge length.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/GreatRhombicosidodecahedron.html">Great Rhombicosidodecahedron</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Truncated_icosidodecahedron">Truncated icosidodecahedron</a>.
%F Equals sqrt(31/4 + 3*sqrt(5)) = sqrt(31/4 + A010499) = sqrt(31 + A344171)/2.
%e 3.802394499851293584766836714110323209303892865251...
%t First[RealDigits[Sqrt[31/4 + Sqrt[45]], 10, 100]] (* or *)
%t First[RealDigits[PolyhedronData["TruncatedIcosidodecahedron", "Circumradius"], 10, 100]]
%Y Cf. A377796 (surface area), A377797 (volume), A377799 (midradius).
%Y Cf. A010499, A344171.
%K nonn,cons,easy
%O 1,1
%A _Paolo Xausa_, Nov 08 2024