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 A053554 #25 Mar 24 2012 13:11:37 %S A053554 1,3,19,195,2791,51303,1152019,30564075,935494831,32447734143, %T A053554 1257770533339,53884306900515,2528224238464471,128934398091500823, %U A053554 7101273378743303779,420078397130637237915,26563302733186339752511 %N A053554 Duplicate of A048172. %K A053554 dead %O A053554 1,2