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 A365652 #12 Nov 04 2023 18:24:49 %S A365652 1,2,19,293,6590,168753 %N A365652 Number of free n-polyominoids, allowing corner-connections only. %C A365652 Two squares are allowed to meet in an edge, but the structure must be connected through pure corner-connections (where the two squares meet in a single point) only. There are 3 such cases of size 3; see the linked illustration. %H A365652 Pontus von Brömssen, <a href="/A365652/a365652.svg">Illustration for sizes 1..3</a>. %H A365652 <a href="/index/Pol#polyominoes">Index entries for sequences related to polyominoes</a>. %Y A365652 Cf. A075679 (polyominoids, edge-connections only), A365650 (corner- and edge-connections), A365653 (fixed). %Y A365652 27th row of A366766. %K A365652 nonn,hard,more %O A365652 1,2 %A A365652 _Pontus von Brömssen_, Sep 17 2023