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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A377750 Decimal expansion of the surface area of a truncated icosahedron with unit edge length.

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%I A377750 #14 Feb 05 2025 10:12:45
%S A377750 7,2,6,0,7,2,5,3,0,3,4,1,3,3,9,2,1,8,7,8,9,3,1,5,3,3,9,7,3,8,3,9,4,8,
%T A377750 6,2,0,1,1,7,2,6,4,7,6,5,4,4,3,3,7,9,8,7,9,2,1,5,9,3,4,5,8,6,7,8,4,4,
%U A377750 4,1,8,4,1,3,7,7,1,5,9,5,8,8,8,4,2,3,6,8,0,4
%N A377750 Decimal expansion of the surface area of a truncated icosahedron with unit edge length.
%H A377750 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TruncatedIcosahedron.html">Truncated Icosahedron</a>.
%H A377750 Wikipedia, <a href="https://en.wikipedia.org/wiki/Truncated_icosahedron">Truncated icosahedron</a>.
%H A377750 <a href="/index/Al#algebraic_08">Index entries for algebraic numbers, degree 8</a>.
%F A377750 Equals 3*(10*sqrt(3) + sqrt(25 + 10*sqrt(5))) = 30*A002194 + 3*sqrt(25 + 10*A002163).
%F A377750 Equals 30*(A002194 + A375067).
%e A377750 72.60725303413392187893153397383948620117264765443...
%t A377750 First[RealDigits[3*(10*Sqrt[3] + Sqrt[25 + Sqrt[500]]), 10, 100]] (* or *)
%t A377750 First[RealDigits[PolyhedronData["TruncatedIcosahedron", "SurfaceArea"], 10, 100]]
%o A377750 (PARI) 3*(10*sqrt(3) + sqrt(25 + 10*sqrt(5))) \\ _Charles R Greathouse IV_, Feb 05 2025
%Y A377750 Cf. A377751 (volume), A377752 (circumradius), A205769 (midradius + 1), A377787 (Dehn invariant).
%Y A377750 Cf. A010527 (analogous for a regular icosahedron, with offset 1).
%Y A377750 Cf. A002163, A002194, A375067.
%K A377750 nonn,cons,easy
%O A377750 2,1
%A A377750 _Paolo Xausa_, Nov 06 2024