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%I #6 Nov 08 2024 11:38:18
%S 1,7,4,2,9,2,0,3,0,3,4,2,3,2,3,9,2,0,8,8,2,9,3,2,1,0,7,5,2,6,2,8,3,4,
%T 6,5,7,2,8,4,8,5,2,2,1,9,2,0,4,4,5,1,9,1,6,5,2,8,4,8,8,9,6,8,9,4,8,0,
%U 3,8,8,9,1,6,2,1,1,6,7,2,8,6,6,6,0,7,2,1,9,7
%N Decimal expansion of the surface area 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 30*(1 + sqrt(3) + sqrt(5 + 2*sqrt(5))) = 30*(A090388 + A019970).
%e 174.292030342323920882932107526283465728485221920...
%t First[RealDigits[30*(1 + Sqrt[3] + Sqrt[5 + Sqrt[20]]), 10, 100]] (* or *)
%t First[RealDigits[PolyhedronData["TruncatedIcosidodecahedron", "SurfaceArea"], 10, 100]]
%Y Cf. A377797 (volume), A377798 (circumradius), A377799 (midradius).
%Y Cf. A090388, A019970.
%K nonn,cons,easy
%O 3,2
%A _Paolo Xausa_, Nov 07 2024