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 A385803 #9 Jul 13 2025 07:06:08 %S A385803 2,1,5,3,4,9,0,1,0,2,4,8,1,1,8,6,2,4,6,1,4,0,8,7,3,5,6,2,7,6,5,0,7,7, %T A385803 6,9,1,1,4,3,0,7,5,4,8,3,4,6,2,7,9,3,4,8,6,2,2,1,0,4,6,4,5,1,8,8,6,8, %U A385803 5,2,2,4,6,4,3,6,1,6,6,2,4,0,6,0,2,7,2,7,7,8 %N A385803 Decimal expansion of the surface area of a parabiaugmented dodecahedron with unit edge. %C A385803 The parabiaugmented dodecahedron is Johnson solid J_59. %C A385803 Also the surface area of a metabiaugmented dodecahedron (Johnson solid J_60) with unit edge. %H A385803 Paolo Xausa, <a href="/A385803/b385803.txt">Table of n, a(n) for n = 2..10000</a> %H A385803 Wikipedia, <a href="https://en.wikipedia.org/wiki/Parabiaugmented_dodecahedron">Parabiaugmented dodecahedron</a>. %F A385803 Equals (5/2)*(sqrt(3) + sqrt(5*(5 + 2*sqrt(5)))) = (5/2)*(A002194 + sqrt(5*(5 + A010476))). %F A385803 Equals the largest root of x^8 - 700*x^6 + 121250*x^4 - 5421875*x^2 + 390625. %e A385803 21.5349010248118624614087356276507769114307548346... %t A385803 First[RealDigits[5/2*(Sqrt[3] + Sqrt[25 + 10*Sqrt[5]]), 10, 100]] (* or *) %t A385803 First[RealDigits[PolyhedronData["J59", "SurfaceArea"], 10, 100]] %Y A385803 Cf. A385802 (volume). %Y A385803 Cf. A002194, A010476, A385696, A385805. %K A385803 nonn,cons,easy %O A385803 2,1 %A A385803 _Paolo Xausa_, Jul 09 2025