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 A144893 #6 Jul 04 2023 13:06:35 %S A144893 1,5,55,360,3630,29820,321300,3225600,38808000,466300800,6360379200, %T A144893 89703936000,1389213504000,22565765376000,394272204480000, %U A144893 7248941973504000,141496402037760000,2901258659819520000,62617333274496000000,1414755114367795200000,33446554797269053440000 %N A144893 Second column (m=2) of triangle A144891 (S1hat(5)). %F A144893 a(n) = A144891(n+2,2), n>=0. %Y A144893 Cf. A144891, A001720 (first column), A144894 (third column). %K A144893 nonn,easy %O A144893 0,2 %A A144893 _Wolfdieter Lang_, Oct 09 2008