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A112389
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Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 2 X 4.
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1
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OFFSET
| 1,2
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COMMENTS
| a(6) is often quoted as 102981500, but this is incorrect.
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REFERENCES
| M. Abrahamsen and S. Eilers, Efficient counting of LEGO buildings, in preparation
B. Durhuus and S. Eilers, On entropy of LEGO, arXiv:math.CO/0504039
Anthony Lane, The Joy of Bricks, New Yorker, Apr 27-May 04, 1998, pp. 96-103.
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LINKS
| S. Eilers, LEGO counts
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CROSSREFS
| Cf. A112390.
Sequence in context: A203973 A063885 A019284 * A187634 A054777 A084224
Adjacent sequences: A112386 A112387 A112388 * A112390 A112391 A112392
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KEYWORD
| nonn,hard
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Dec 06 2005
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EXTENSIONS
| Thanks to Gerald McGarvey, Christian Schroeder and Jud McCranie who contributed to this entry.
a(8) from Soren Eilers (eilers(AT)math.ku.dk), Oct 29 2006
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