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 A378976 #8 Dec 15 2024 07:24:51 %S A378976 1,3,9,4,4,2,7,1,9,0,9,9,9,9,1,5,8,7,8,5,6,3,6,6,9,4,6,7,4,9,2,5,1,0, %T A378976 4,9,4,1,7,6,2,4,7,3,4,3,8,4,4,6,1,0,2,8,9,7,0,8,3,5,8,8,9,8,1,6,4,2, %U A378976 0,8,3,7,0,2,5,5,1,2,1,9,5,9,7,6,5,7,6,5,7,6 %N A378976 Decimal expansion of the midradius of a triakis icosahedron with unit shorter edge length. %C A378976 The triakis icosahedron is the dual polyhedron of the truncated dodecahedron. %H A378976 Paolo Xausa, <a href="/A378976/b378976.txt">Table of n, a(n) for n = 1..10000</a> %H A378976 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TriakisIcosahedron.html">Triakis Icosahedron</a>. %H A378976 Wikipedia, <a href="https://en.wikipedia.org/wiki/Triakis_icosahedron">Triakis icosahedron</a>. %F A378976 Equals 1/2 + 2/sqrt(5) = 1/2 + 2/A002163. %F A378976 Equals (A249600 + 13)/10 = (A010532 + 5)/10. %e A378976 1.3944271909999158785636694674925104941762473438446... %t A378976 First[RealDigits[1/2 + 2/Sqrt[5], 10, 100]] (* or *) %t A378976 First[RealDigits[PolyhedronData["TriakisIcosahedron", "Midradius"], 10, 100]] %Y A378976 Cf. A378973 (surface area), A378974 (volume), A378975 (inradius), A378977 (dihedral angle). %Y A378976 Cf. A377697 (midradius of a truncated dodecahedron with unit edge length). %Y A378976 Cf. A002163, A010532, A249600. %K A378976 nonn,cons,easy %O A378976 1,2 %A A378976 _Paolo Xausa_, Dec 14 2024