

A216595


Number of distinct connected planar figures that can be formed from 1 X 2 rectangles (or dominoes) such that each pair of touching rectangles shares exactly one edge, of length 1.


6




OFFSET

0,2


COMMENTS

Figures that differ by a rotation or reflection are regarded as distinct (cf. A216583).
This sequence is A216581 without the condition that the adjacency graph of the dominoes forms a tree.
An example: The two solutions
V H 
 V
H  
and
H  V
V 
 H 
are considered to be the same because the resulting shape is the same.


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CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



