OFFSET
1,4
REFERENCES
M. Gardner, Tiling with Polyominoes, Polyiamonds and Polyhexes. Chap. 14 in Time Travel and Other Mathematical Bewilderments. New York: W. H. Freeman, pp. 175-187, 1988.
LINKS
Joseph Myers, Polyiamond tiling
CROSSREFS
KEYWORD
hard,nonn
AUTHOR
Joseph Myers, May 19 2002
EXTENSIONS
More terms from Joseph Myers, Nov 11 2003
a(29) and a(30) from Joseph Myers, Nov 21 2010
STATUS
approved