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%I #6 Sep 25 2024 09:52:37
%S 0,0,0,0,0,0,1,5,35,179,909,4287,19723,88240,388260,1683998,7227374,
%T 30750236
%N The number of free kissing polyominoes with n cells.
%C 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 The sequence differs from A359520 (Number of free holey polyominoes of n cells with simply-connected interiors) at a(12) because of:
%C OOOO OOO
%C O O O O OO
%C OOOOO OO O
%C OOO
%C which are kissing (and hence holey) but do not have simply-connected interiors.
%Y Cf. A367557, A359520.
%K nonn,more
%O 1,8
%A _John Mason_, Sep 25 2024