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.
LINKS
César E. Lozada, Illustration of terms n <= 4 of A216583
Manfred Scheucher, Python Script
N. J. A. Sloane, Illustration of initial terms of A056786, A216598, A216583, A216595, A216492, A216581 (Exclude figures marked (A))
N. J. A. Sloane, Illustration of third term of A056786, A216598, A216583, A216595, A216492, A216581 (a better drawing for the third term)
M. Vicher, Polyforms
CROSSREFS
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Sep 08 2012
EXTENSIONS
Terms a(4)-a(6) added by César Eliud Lozada, Sep 09 2012
STATUS
approved