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A075223
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Number of polyiamonds with n cells that tile the plane isohedrally.
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10
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1, 1, 1, 3, 4, 12, 23, 66, 133, 316, 514, 1987, 2398, 6073, 12628, 29918, 26211, 108778, 95348, 375045, 498168, 780434, 843319, 4981628, 3691212, 7357764, 13169722, 33461765, 22372303, 117437124
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,4
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COMMENTS
| A tiling is isohedral if the symmetries of the tiling act transitively on the tiles; a shape is anisohedral if it tiles the plane, but not isohedrally.
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REFERENCES
| Branko Gruenbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Section 9.4.
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LINKS
| Joseph Myers, Polyiamond tiling
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CROSSREFS
| Cf. A071332, A075216, A075217, A075218, A075219, A075220, A075221, A075222, A075224, A075205, A075214.
Sequence in context: A129922 A005221 A000206 * A071332 A006791 A111358
Adjacent sequences: A075220 A075221 A075222 * A075224 A075225 A075226
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KEYWORD
| hard,nonn
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AUTHOR
| Joseph Myers (jsm(AT)polyomino.org.uk), Sep 08 2002
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EXTENSIONS
| More terms from Joseph Myers (jsm(AT)polyomino.org.uk), Nov 11 2003
a(29) and a(30) from Joseph Myers (jsm(AT)polyomino.org.uk), Nov 21 2010
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