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
KEYWORD
hard,nonn
AUTHOR
Joseph Myers, Oct 16 2011
STATUS
approved