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 A027148 #7 Oct 24 2019 16:01:04 %S A027148 1,6,20,152,528,4416,15488,135552,477440,4289536,15144960,138407936, %T A027148 489431040,4526702592,16024403968,149528084480,529747476480, %U A027148 4977103994880,17643662213120,166668216041472,591119702294528,5608619676532736 %N A027148 a(n) = A027144(2n-1, n-1). %K A027148 nonn %O A027148 1,2 %A A027148 _Clark Kimberling_