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 A376496 #6 Sep 25 2024 09:52:37 %S A376496 0,0,0,0,0,0,1,5,35,179,909,4287,19723,88240,388260,1683998,7227374, %T A376496 30750236 %N A376496 The number of free kissing polyominoes with n cells. %C A376496 A polyomino is 'kissing' if there exist two cells that touch only at a corner such that no cell exists touching both edgewise simultaneously. %C A376496 The sequence differs from A359520 (Number of free holey polyominoes of n cells with simply-connected interiors) at a(12) because of: %C A376496 OOOO OOO %C A376496 O O O O OO %C A376496 OOOOO OO O %C A376496 OOO %C A376496 which are kissing (and hence holey) but do not have simply-connected interiors. %Y A376496 Cf. A367557, A359520. %K A376496 nonn,more %O A376496 1,8 %A A376496 _John Mason_, Sep 25 2024