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 A119280 #9 Feb 16 2025 08:33:01 %S A119280 1,3,5,5,4,6,1,8,0,4,7,0,6,4,0,8,7,4,3,8,6,3,4,4,1,5,3,5,9,1,0,9,7,0, %T A119280 9,7,6,0,3,6,7,9,0,2,7,1,0,4,7,9,9,3,1,7,8,1,6,1,7,9,3,6,6,8,1,3,3,0, %U A119280 5,8,8,1,9,0,4,3,0,2,0,3,7,1,2,8,5,4,2,1,2,4,7,7,9,8,8,9,0,1,1,5,7,5,1,3,9 %N A119280 Decimal expansion of Feigenbaum kappa constant. %H A119280 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/FeigenbaumConstant.html">Feigenbaum Constant</a> %e A119280 1.3554618047064087438... %Y A119280 Cf. A119277, A119278, A119279. %K A119280 nonn,cons %O A119280 1,2 %A A119280 _Eric W. Weisstein_, May 12 2006