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Number of free n-celled polyiamonds to which two inequivalent cells can be adjoined such that the two resulting free (n+1)-celled polyiamonds are identical.
3

%I #6 Jun 14 2024 12:16:06

%S 0,0,0,0,1,0,0,3,0,1,8,0,6,24,1,22

%N Number of free n-celled polyiamonds to which two inequivalent cells can be adjoined such that the two resulting free (n+1)-celled polyiamonds are identical.

%C Two cells that can be adjoined to an n-celled polyiamond are equivalent if there is an isomorphism between the two resulting (n+1)-celled polyiamonds that maps the adjoined cell of the first to the adjoined cell of the second.

%H Pontus von Brömssen, <a href="/A373637/a373637.svg">Illustration up to n = 13</a>.

%H <a href="/index/Pol#polyominoes">Index entries for sequences related to polyominoes</a>.

%Y Cf. A369366, A373635, A373636.

%K nonn,more

%O 1,8

%A _Pontus von Brömssen_, Jun 13 2024