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 A181051 #23 Nov 30 2020 03:57:32 %S A181051 4,2,7,0,3,8,5,9,0,2,1,6,7,2,4,8,7,0,8,6,1,4,0,4,7,3,1,0,3,9,5,6,4,0, %T A181051 1,4,6,1,4,1,5,1,9,7,0,6,8,6,5,1,8,2,7 %N A181051 Incorrect duplicate of A073821. %C A181051 Previous name was: Decimal expansion of the constant whose continued fraction representation is [0; 2, 4, 6, 8, ..., 2*n, ...], i.e., 2/(4+6/(8+10/(12+...) using every even integer. %e A181051 0.42703859021672487086140473103956401461415197068651827... %K A181051 dead %O A181051 0,1 %A A181051 _Jonathan D. B. Hodgson_, Oct 01 2010