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 A379891 #8 Jan 10 2025 06:13:46 %S A379891 3,5,9,7,6,2,4,8,2,2,5,5,1,1,8,9,0,1,1,4,2,8,2,5,6,5,5,9,4,4,4,4,2,3, %T A379891 5,3,8,4,1,1,9,6,4,5,2,2,6,6,7,7,7,1,0,1,3,4,7,6,9,9,5,5,7,8,3,0,1,6, %U A379891 3,6,8,7,3,2,6,0,4,5,1,3,1,6,2,5,1,7,4,2,0,6 %N A379891 Decimal expansion of the midradius of a pentagonal hexecontahedron with unit shorter edge length. %C A379891 The pentagonal hexecontahedron is the dual polyhedron of the snub dodecahedron. %H A379891 Paolo Xausa, <a href="/A379891/b379891.txt">Table of n, a(n) for n = 1..10000</a> %H A379891 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PentagonalHexecontahedron.html">Pentagonal Hexecontahedron</a>. %H A379891 Wikipedia, <a href="https://en.wikipedia.org/wiki/Pentagonal_hexecontahedron">Pentagonal hexecontahedron</a>. %F A379891 Equals the largest real root of 4096*x^12 - 58368*x^10 + 70656*x^8 - 17728*x^6 + 1392*x^4 - 120*x^2 + 1. %e A379891 3.59762482255118901142825655944442353841196452... %t A379891 First[RealDigits[Root[4096*#^12 - 58368*#^10 + 70656*#^8 - 17728*#^6 + 1392*#^4 - 120*#^2 + 1 &, 8], 10, 100]] (* or *) %t A379891 First[RealDigits[PolyhedronData["PentagonalHexecontahedron", "Midradius"], 10, 100]] %Y A379891 Cf. A379888 (surface area), A379889 (volume), A379890 (inradius), A379892 (dihedral angle). %Y A379891 Cf. A377807 (midradius of a snub dodecahedron with unit edge length). %K A379891 nonn,cons,easy %O A379891 1,1 %A A379891 _Paolo Xausa_, Jan 09 2025