A123847 - OEIS

A123847

Number of ways to build a contiguous building with n LEGO blocks of size 5x5 on top of a fixed block of the same size.

%I #7 Oct 09 2013 14:20:53

%S 81,7981,1031121,144390851,21872530449,3453512003039

%N Number of ways to build a contiguous building with n LEGO blocks of size 5x5 on top of a fixed block of the same size.

%C The base block is not counted among the n and must be the only block in the bottom layer of the building

%H M. Abrahamsen and S. Eilers, <a href="http://dx.doi.org/10.1080/10586458.2011.564539">On the asymptotic enumeration of LEGO Structures</a>, Exper. Math. 20 (2) (2011) 145-152

%H Durhuus and S. Eilers, <a href="http://arxiv.org/abs/math.CO/0504039">On the entropy of LEGO</a>, arXiv:math.CO/0504039

%K nonn,hard

%O 1,1

%A _Søren Eilers_, Oct 29 2006