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 A169785 #6 Jan 31 2019 20:07:16 %S A169785 1,7,31,127,499,1975,7855,31327,125119,500083,1999507,7996327 %N A169785 A151723(2^n). %C A169785 High water marks in A151723. %F A169785 a(n) = 6*A169781(n) -6*2^n + 1. %Y A169785 Cf. A151723, A169781. %K A169785 nonn %O A169785 0,2 %A A169785 _N. J. A. Sloane_, May 12 2010 %E A169785 a(11) from Mike Warburton, Jan 31 2019.