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%I #10 Nov 11 2024 08:05:55
%S 5,5,2,8,6,7,4,4,9,5,8,4,4,5,1,4,8,9,4,3,6,5,7,0,7,0,5,5,8,7,8,0,7,6,
%T 2,5,3,1,7,4,4,5,9,5,1,1,6,3,2,9,9,9,2,5,1,1,6,0,1,2,7,6,0,7,3,3,2,5,
%U 0,8,8,2,4,4,6,8,3,5,9,5,5,1,7,6,1,2,2,1,8,6
%N Decimal expansion of the surface area of a snub dodecahedron with unit edge length.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SnubDodecahedron.html">Snub Dodecahedron</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Snub_dodecahedron">Snub dodecahedron</a>.
%F Equals 20*sqrt(3) + 3*sqrt(25 + 10*sqrt(5)) = 20*A002194 + A131595.
%e 55.2867449584451489436570705587807625317445951163...
%t First[RealDigits[20*Sqrt[3] + 3*Sqrt[25 + 10*Sqrt[5]], 10, 100]] (* or *)
%t First[RealDigits[PolyhedronData["SnubDodecahedron", "SurfaceArea"], 10, 100]]
%Y Cf. A377805 (volume), A377806 (circumradius), A377807 (midradius).
%Y Cf. A131595 (analogous for a regular dodecahedron).
%Y Cf. A002194.
%K nonn,cons,easy
%O 2,1
%A _Paolo Xausa_, Nov 08 2024