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 A385448 #9 Jul 03 2025 01:09:19 %S A385448 1,2,1,8,2,7,8,8,8,7,3,5,9,6,6,2,2,9,1,5,3,5,4,6,0,2,6,7,9,1,7,2,7,4, %T A385448 7,4,5,2,0,3,6,8,7,4,0,0,5,3,1,5,5,4,3,5,6,6,6,6,9,9,1,9,0,4,7,5,6,9, %U A385448 3,9,7,6,5,7,4,7,5,7,2,2,2,0,5,8 %N A385448 Decimal expansion of sqrt(5 + 7*phi)/sqrt(11), with the golden section phi = A001622. %C A385448 This equals the ratio length(Z, D_1)/s, with the fixed point of a complex loxodromic map w mapping iteratively golden triangles, starting with the one inscribed in a circumcircle with center ot the origin of the complex plane, the top vertex D_1 = i (the complex unit) and the base D_2 = (s - phi*i)/2, D_3 = (-s - phi*i)/2, with s = A182007. %C A385448 See A385445 for details and a linked paper. %F A385448 Equals sqrt(5 + 7*phi)/sqrt(11) = sqrt(5 + 7*phi)/A010468. %F A385448 Equals A385447/(A010468*A182007). %e A385448 1.218278887359662291535460267917274745203687400531554... %t A385448 RealDigits[Sqrt[(5 + 7*GoldenRatio)/11], 10, 120][[1]] (* _Amiram Eldar_, Jul 02 2025 *) %Y A385448 Cf. A001622, A182007, A010468, A385445. %K A385448 nonn,cons,easy %O A385448 1,2 %A A385448 _Wolfdieter Lang_, Jul 01 2025