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 A188659 #27 Feb 11 2025 15:18:21 %S A188659 1,2,1,9,8,0,3,9,0,2,7,1,8,5,5,6,9,6,6,0,0,5,6,4,4,8,2,1,8,0,4,5,5,6, %T A188659 3,9,7,9,1,2,7,5,4,1,8,9,2,1,9,9,1,9,2,8,1,5,1,6,9,9,4,1,6,0,8,8,5,1, %U A188659 8,6,7,2,6,4,1,2,4,4,4,8,3,9,1,1,7,6,6,9,7,7,0,2,1,8,7,8,6,4,0,1,6,7,2,2,3,8,0,5,1,6,4,8,2,0,7,9,8,2,1,3,2,2,8,6,3,5,5,8,6,8 %N A188659 Decimal expansion of (1+sqrt(26))/5. %C A188659 Decimal expansion of the shape of a (2/5)-extension rectangle; see A188640 for definitions of shape and r-extension rectangle. Briefly, shape=length/width, and an r-extension rectangle is composed of two rectangles of shape 1/r when r<1. %C A188659 The continued fraction of the constant is 1, 4, 1, 1, 4, 1, ... = A146325. %H A188659 <a href="/index/Al#algebraic_02">Index entries for algebraic numbers, degree 2</a>. %F A188659 Equals exp(arcsinh(1/5)). - _Amiram Eldar_, Jul 04 2023 %e A188659 1.219803902718556966005644821804556397912754189219919281516994... %t A188659 RealDigits[(1 + Sqrt[26])/5, 10, 111][[1]] (* _Robert G. Wilson v_, Aug 18 2011 *) %Y A188659 Cf. A146325, A188640, A188658, A188729, A188730, A010481. %K A188659 nonn,cons,easy %O A188659 1,2 %A A188659 _Clark Kimberling_, Apr 09 2011