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 A088743 #4 Oct 19 2017 03:14:25 %S A088743 1,3,5,5,7,9,9,9,11,13,15,15,15,17,17,17,19,21,23,23,25,27,27,27,27, %T A088743 29,31,31,31,33,33,33 %N A088743 a(n) = 2*A088023(n) - 1. %Y A088743 Cf. A088023. %K A088743 nonn %O A088743 1,2 %A A088743 _Gary W. Adamson_, Oct 12 2003 %E A088743 Edited by _Don Reble_, Nov 13 2005