OFFSET
0,2
COMMENTS
This is the result of trying to infer the rules behind A056755. The match is not exact - these rules allow 16 3-celled polyominoes not allowed in A056755. However, the reason for the exclusion of those 16 polyominoes in A056755 is not clear.
The restrictions are: all curved edges must be on the boundary of the polyomino, each side of the polyomino must be either all curved, or all straight and if two cells meet on a side of length 2, they must share the whole side. Polyominoes are allowed to be rotated and reflected.
See the Applegate link for further information.
LINKS
David Applegate, Explanation of rules; examples; differences from A056755
M. Vicher, Polyforms
M. Vicher, The 10 2-celled polyominoes mentioned in A056755 [Taken from the Vicher web site]
M. Vicher, The 68 3-celled polyominoes mentioned in A056755 [Taken from the Vicher web site]
CROSSREFS
KEYWORD
nice,nonn,more
AUTHOR
STATUS
approved