OFFSET
1,9
COMMENTS
Two cells that can be adjoined to an n-celled polyomino are equivalent if there is an isomorphism between the two resulting (n+1)-celled polyominoes that maps the adjoined cell of the first to the adjoined cell of the second.
LINKS
EXAMPLE
The smallest example is the P pentomino shown below. The two free hexominoes obtained by adjoining one of the two cells marked "*" are identical, but there is no isomorphism between them that also maps the marked cell of the first to the marked cell of the second.
_ _
*| |
| _|*
|_|
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Pontus von Brömssen, Jun 13 2024
STATUS
approved