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 A378390 #8 Feb 11 2025 09:56:55 %S A378390 3,0,6,9,4,8,9,5,7,2,4,0,3,1,0,0,9,5,9,0,7,7,0,3,1,4,7,8,4,0,5,0,6,7, %T A378390 3,3,8,7,9,6,5,1,0,7,4,6,3,1,6,1,0,1,8,7,7,3,0,7,0,1,5,3,8,6,7,0,2,7, %U A378390 7,7,1,9,8,7,8,9,1,2,5,1,5,6,7,7,9,0,3,1,3,6 %N A378390 Decimal expansion of the surface area of a deltoidal icositetrahedron with unit shorter edge length. %C A378390 The deltoidal icositetrahedron is the dual polyhedron of the (small) rhombicuboctahedron. %H A378390 Paolo Xausa, <a href="/A378390/b378390.txt">Table of n, a(n) for n = 2..10000</a> %H A378390 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DeltoidalIcositetrahedron.html">Deltoidal Icositetrahedron</a>. %H A378390 Wikipedia, <a href="https://en.wikipedia.org/wiki/Deltoidal_icositetrahedron">Deltoidal icositetrahedron</a>. %H A378390 <a href="/index/Al#algebraic_04">Index entries for algebraic numbers, degree 4</a>. %F A378390 Equals 6*sqrt(29 - 2*sqrt(2)) = 6*sqrt(29 - A010466). %e A378390 30.694895724031009590770314784050673387965107463161... %t A378390 First[RealDigits[6*Sqrt[29 - Sqrt[8]], 10, 100]] (* or *) %t A378390 First[RealDigits[PolyhedronData["DeltoidalIcositetrahedron", "SurfaceArea"], 10, 100]] %Y A378390 Cf. A378391 (volume), A378392 (inradius), A378393 (midradius), A378394 (dihedral angle). %Y A378390 Cf. A343964 (surface area of a (small) rhombicuboctahedron with unit edge). %Y A378390 Cf. A010466. %K A378390 nonn,cons,easy %O A378390 2,1 %A A378390 _Paolo Xausa_, Nov 29 2024