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 A366339 #11 Dec 04 2023 01:35:35 %S A366339 6,48,592,8664,140088,2414056 %N A366339 Number of fixed (4,2)-polyominoids with n cells, allowing right-angled (or hard) connections only. %C A366339 Two squares sharing an edge have a right-angled connection if they do not lie in the same plane. %C A366339 Connections that are not right-angled (flat connections) may occur, but the polyominoids considered here must be connected through right-angled connections only. %H A366339 Wikipedia, <a href="https://en.wikipedia.org/wiki/Polyominoid">Polyominoid</a>. %H A366339 <a href="/index/Pol#polyominoes">Index entries for sequences related to polyominoes</a>. %Y A366339 Cf. A075678, A365655, A366335, A366338 (free), A366341. %Y A366339 45th row of A366767. %K A366339 nonn,hard,more %O A366339 1,1 %A A366339 _Pontus von Brömssen_, Oct 07 2023