|
|
A213950
|
|
Number of free poly-IH9-tiles (holes allowed) with n cells.
|
|
0
|
|
|
1, 2, 7, 24, 99, 416, 1852, 8386, 38798, 181531, 858570, 4092042, 19636172, 94750922
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
REFERENCES
|
Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Sections 6.2 and 9.4.
|
|
LINKS
|
|
|
CROSSREFS
|
|
|
KEYWORD
|
hard,nonn,more
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|