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A075221
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Number of polyiamonds with n cells that tile the plane by translation or by 180-degree rotation (Conway criterion).
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10
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1, 1, 1, 3, 4, 12, 21, 56, 111, 262, 462, 1453, 1875, 4734, 9410, 20603, 24034, 79352, 79925, 273731, 358096, 669640, 796571, 3342349, 2980476, 6387513, 10167660, 24999509, 21477012, 87978317
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,4
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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, A075222, A075223, A075224, A075203, A075212.
Sequence in context: A026553 A101727 A075220 * A129922 A005221 A000206
Adjacent sequences: A075218 A075219 A075220 * A075222 A075223 A075224
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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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