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 A053551 #4 Mar 30 2012 16:48:45 %S A053551 1,4,12,128,-2360,225504,-31479056,7663698176,-3268091071872, %T A053551 2502155367185920,-3525130171601665792,9336272433375180957696, %U A053551 -47283253230423958235278336,463782058088334028985937178624,-8890882429150197015851583349985280 %N A053551 REVEGF transform of [1,2,12,152,3640,...] (A053549). %K A053551 sign %O A053551 1,2 %A A053551 _N. J. A. Sloane_, Jan 16 2000