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 A144345 #7 Jul 04 2023 08:18:10 %S A144345 1,6,52,600,8680,151200,3082240,71998080,1896294400,55601145600, %T A144345 1796277683200,63397990656000,2427084884224000,100175046107136000, %U A144345 4434284662872064000,209554432423784448000,10530302071553904640000,560682451860226375680000 %N A144345 Second column (m=2) of triangle S2p(-2) = A004747. %F A144345 a(n) = A004747(n+2,2), n>=0. %Y A144345 Cf. A004747, A008544(n-1) (m=1 column), A144346 (m=3 column). %K A144345 nonn,easy %O A144345 0,2 %A A144345 _Wolfdieter Lang_, Oct 09 2008