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 A379387 #8 Dec 24 2024 08:43:21 %S A379387 2,6,3,4,7,9,7,6,8,8,2,2,2,4,7,1,3,6,5,0,1,3,7,9,3,3,3,7,4,7,5,9,8,0, %T A379387 2,6,5,5,7,0,2,7,8,7,1,5,8,8,4,4,6,5,9,1,1,8,4,4,2,4,5,0,9,9,4,1,6,2, %U A379387 3,4,6,6,9,6,9,0,0,8,7,6,3,3,7,1,4,5,2,5,7,7 %N A379387 Decimal expansion of the inradius of a deltoidal hexecontahedron with unit shorter edge length. %C A379387 The deltoidal hexecontahedron is the dual polyhedron of the (small) rhombicosidodecahedron. %H A379387 Paolo Xausa, <a href="/A379387/b379387.txt">Table of n, a(n) for n = 1..10000</a> %H A379387 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DeltoidalHexecontahedron.html">Deltoidal Hexecontahedron</a>. %H A379387 Wikipedia, <a href="https://en.wikipedia.org/wiki/Deltoidal_hexecontahedron">Deltoidal hexecontahedron</a>. %F A379387 Equals 11*sqrt((135 + 59*sqrt(5))/205)/(7 - sqrt(5)) = 11*sqrt((135 + 59*A002163)/205)/(7 - A002163). %F A379387 Equals the largest root of 820*x^4 - 5710*x^2 + 121. %e A379387 2.634797688222471365013793337475980265570278715884... %t A379387 First[RealDigits[Root[820*#^4 - 5710*#^2 + 121 &, 4], 10, 100]] (* or *) %t A379387 First[RealDigits[PolyhedronData["DeltoidalHexecontahedron", "Inradius"], 10, 100]] %Y A379387 Cf. A379385 (surface area), A379386 (volume), A379388 (midradius), A379389 (dihedral angle). %Y A379387 Cf. A002163. %K A379387 nonn,cons,easy %O A379387 1,1 %A A379387 _Paolo Xausa_, Dec 23 2024