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 A377296 #14 Nov 20 2024 23:44:24 %S A377296 2,2,9,2,7,5,9,8,8,3,4,9,8,8,2,2,2,6,7,5,9,3,2,5,7,0,4,6,0,3,7,8,1,8, %T A377296 6,1,0,1,8,4,1,9,5,2,6,8,0,2,4,0,1,3,1,7,8,3,0,3,2,7,5,5,1,0,3,7,2,5, %U A377296 8,8,9,1,0,1,6,9,5,4,3,4,9,2,9,2,9,7,3,9,8,4 %N A377296 Decimal expansion of 24*arctan(sqrt(2)). %C A377296 Dehn invariant of a regular octahedron and (small) rhombicuboctahedron with unit edge and (negated) of a cuboctahedron and truncated cube with unit edge. %H A377296 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DehnInvariant.html">Dehn Invariant</a>. %H A377296 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Cuboctahedron.html">Cuboctahedron</a>. %H A377296 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RegularOctahedron.html">Regular Octahedron</a>. %H A377296 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SmallRhombicuboctahedron.html">Small Rhombicuboctahedron</a>. %H A377296 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TruncatedCube.html">Truncated Cube</a>. %H A377296 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a> %F A377296 Equals 24*A195696 = 2*A377277. %e A377296 22.9275988349882226759325704603781861018419526802... %t A377296 First[RealDigits[24*ArcTan[Sqrt[2]], 10, 100]] (* or *) %t A377296 First[RealDigits[PolyhedronData["Octahedron", "DehnInvariant"], 10, 100]] %o A377296 (PARI) 24*atan(sqrt(2)) \\ _Charles R Greathouse IV_, Nov 20 2024 %Y A377296 Cf. A195696, A377277. %K A377296 nonn,cons,easy %O A377296 2,1 %A A377296 _Paolo Xausa_, Oct 24 2024