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A071332
Number of polyiamonds with n cells that tile the plane.
11
1, 1, 1, 3, 4, 12, 23, 66, 139, 341, 567, 2034, 2495, 6354, 12908, 30261, 26556, 110145, 95967, 377523, 499672, 788726, 845130, 4998370, 3694670, 7406217, 13175181, 33557076, 22381719, 117770863
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.
CROSSREFS
Equals A000577-A071333 and equals A070765-A071334, cf. A054359, A070766.
Sequence in context: A368031 A240737 A075223 * A006791 A111358 A111357
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

  NODES
COMMUNITY 1
INTERN 1