

A123762


Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 1 X 2.


64



1, 4, 37, 375, 4493, 56848, 753536, 10283622, 143607345, 2041497919, 29446248496, 429858432108
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..12.
M. Abrahamsen and S. Eilers, On the asymptotic enumeration of LEGO structures, Exper Math. 20 (2) (2011) 145152.
B. Durhuus and S. Eilers, On the entropy of LEGO, arXiv:math/0504039 [math.CO], 2005.
B. Durhuus and S. Eilers, On the entropy of LEGO, J. Appl. Math. Comput. 45 (12) (2014), 433448.
S. Eilers, A LEGO Counting problem, 2005.
S. Eilers, The LEGO counting problem, Amer. Math. Monthly, 123 (May 2016), 415426.
Index entry for sequences related to LEGO blocks


CROSSREFS

Cf. A007576, A082679, A112389, A112390.
Sequence in context: A197966 A199690 A133462 * A326014 A220914 A070768
Adjacent sequences: A123759 A123760 A123761 * A123763 A123764 A123765


KEYWORD

nonn,hard,more


AUTHOR

Søren Eilers, Oct 29 2006


STATUS

approved



