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A197626
Number of free poly-IH61 tiles (holes allowed) with n cells.
0
1, 1, 4, 11, 35, 110, 392, 1372, 4998, 18251, 67792, 253043, 952534, 3602846, 13699554, 52298066
OFFSET
1,3
COMMENTS
Equivalently, one-sided poly-IH73-tiles.
REFERENCES
Branko Gruenbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Sections 6.2 and 9.4.
CROSSREFS
Cf. A056779.
Sequence in context: A036364 A295247 A052550 * A349185 A358826 A212910
KEYWORD
hard,nonn
AUTHOR
Joseph Myers, Oct 16 2011
STATUS
approved