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%I #7 Nov 06 2024 04:40:31
%S 1,0,0,9,9,0,7,6,0,1,5,3,1,0,1,9,8,8,5,4,4,7,4,5,9,4,8,9,8,8,6,3,6,6,
%T 5,6,5,5,4,9,1,5,0,9,0,5,7,5,1,8,5,6,7,5,9,5,1,4,5,3,7,2,2,4,0,8,5,0,
%U 5,5,6,3,7,3,9,3,9,6,7,2,7,7,3,9,0,4,3,5,4,2
%N Decimal expansion of the surface area of a truncated dodecahedron with unit edge length.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TruncatedDodecahedron.html">Truncated Dodecahedron</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Truncated_dodecahedron">Truncated dodecahedron</a>.
%F Equals 5*(sqrt(3) + 6*sqrt(5 + 2*sqrt(5))) = 5*(A002194 + 6*sqrt(5 + A010476)).
%e 100.990760153101988544745948988636656554915090575...
%t First[RealDigits[5*(Sqrt[3] + 6*Sqrt[5 + Sqrt[20]]), 10, 100]] (* or *)
%t First[RealDigits[PolyhedronData["TruncatedDodecahedron", "SurfaceArea"], 10, 100]]
%Y Cf. A377695 (volume), A377696 (circumradius), A377697 (midradius), A377698 (Dehn invariant, negated).
%Y Cf. A131595 (analogous for a regular dodecahedron).
%Y Cf. A002194, A010476.
%K nonn,cons,easy
%O 3,4
%A _Paolo Xausa_, Nov 04 2024