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 A167553 #4 Jun 02 2025 02:10:36 %S A167553 3,-5,14,-66,308,-2132,14064,-126480,1081632,-11925792,125458560, %T A167553 -1636387200,20447873280,-307814964480 %N A167553 The second right hand column of triangle A167552. %Y A167553 Equals the second right hand column of triangle A167552. %K A167553 sign %O A167553 2,1 %A A167553 _Johannes W. Meijer_, Nov 10 2009