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 A379132 #12 Feb 05 2025 10:22:58 %S A379132 2,7,9,3,5,2,4,9,6,0,0,7,0,0,7,9,3,1,0,5,8,1,0,1,9,1,2,7,9,9,6,3,6,8, %T A379132 0,7,0,5,2,5,7,7,8,6,1,0,9,0,7,3,6,2,6,2,5,3,5,8,6,5,9,8,4,3,0,7,7,6, %U A379132 1,1,3,9,5,8,0,3,1,2,7,3,3,1,2,7,0,1,6,9,7,5 %N A379132 Decimal expansion of the surface area of a pentakis dodecahedron with unit shorter edge length. %C A379132 The pentakis dodecahedron is the dual polyhedron of the truncated icosahedron. %H A379132 Paolo Xausa, <a href="/A379132/b379132.txt">Table of n, a(n) for n = 2..10000</a> %H A379132 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PentakisDodecahedron.html">Pentakis Dodecahedron</a>. %H A379132 Wikipedia, <a href="https://en.wikipedia.org/wiki/Pentakis_dodecahedron">Pentakis dodecahedron</a>. %H A379132 <a href="/index/Al#algebraic_04">Index entries for algebraic numbers, degree 4</a>. %F A379132 Equals (5/3)*sqrt((421 + 63*sqrt(5))/2) = (5/3)*sqrt((421 + 63*A002163)/2). %e A379132 27.93524960070079310581019127996368070525778610907... %t A379132 First[RealDigits[5/3*Sqrt[(421 + 63*Sqrt[5])/2], 10, 100]] (* or *) %t A379132 First[RealDigits[PolyhedronData["PentakisDodecahedron", "SurfaceArea"], 10, 100]] %o A379132 (PARI) sqrt((421 + 63*sqrt(5))/2)*5/3 \\ _Charles R Greathouse IV_, Feb 05 2025 %Y A379132 Cf. A379133 (volume), A379134 (inradius), A379135 (midradius), A379136 (dihedral angle). %Y A379132 Cf. A377750 (surface area of a truncated icosahedron with unit edge length). %Y A379132 Cf. A002163. %K A379132 nonn,cons,easy %O A379132 2,1 %A A379132 _Paolo Xausa_, Dec 16 2024