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.
%I A232809 #26 Aug 21 2023 11:46:13 %S A232809 5,1,4,8,3,4,8,5,5,6,1,9,9,5,1,5,6,4,6,3,3,0,8,1,2,9,4,6,1,1,6,0,1,9, %T A232809 0,6,4,1,0,0,8,6,4,1,1,6,3,8,6,7,2,4,1,4,8,4,5,0,7,1,3,6,7,5,3,9,8,0, %U A232809 3,2,4,7,9,0,5,0,8,5,7,7,1,3,0,2,9,8,3,7,3,2,5,6,2,9,9,4,3,1,0,9,6,7,4,0,0 %N A232809 Decimal expansion of the surface index of a regular icosahedron. %C A232809 Equivalently, surface area of a regular icosahedron with unit volume. Among Platonic solids, surface indices decrease with increasing number of faces: A232812 (tetrahedron), 6.0 (cube = hexahedron), A232811 (octahedron), A232810 (dodecahedron), and this one. %C A232809 An algebraic integer of degree 12 with minimal polynomial x^12 - 41115600x^6 + 765275040000. - _Charles R Greathouse IV_, Apr 25 2016 %H A232809 Stanislav Sykora, <a href="/A232809/b232809.txt">Table of n, a(n) for n = 1..1000</a> %H A232809 Wikipedia, <a href="http://en.wikipedia.org/wiki/Platonic_solid">Platonic solid</a>. %H A232809 <a href="/index/Al#algebraic_12">Index entries for algebraic numbers, degree 12</a> %F A232809 Equals 5*sqrt(3)/(5*(3+sqrt(5))/12)^(2/3). %F A232809 Equals 10*A010527/A102208^(2/3). %e A232809 5.14834855619951564633081294611601906410086411638672414845... %t A232809 RealDigits[5*Sqrt[3]/(5*(3+Sqrt[5])/12)^(2/3), 10, 120][[1]] (* _Amiram Eldar_, May 25 2023 *) %o A232809 (PARI) 5*sqrt(3)/(5*(3+sqrt(5))/12)^(2/3) \\ _Charles R Greathouse IV_, Apr 25 2016 %Y A232809 Cf. A010527, A102208 (solid index of a sphere), A232808, A232810, A232811, A232812. %K A232809 nonn,cons,easy %O A232809 1,1 %A A232809 _Stanislav Sykora_, Dec 01 2013