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.

81, 7981, 1031121, 144390851, 21872530449, 3453512003039 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	COMMENTS	`The base block is not counted among the n and must be the only block in the bottom layer of the building`
	LINKS	`Table of n, a(n) for n=1..6.` `M. Abrahamsen and S. Eilers, On the asymptotic enumeration of LEGO Structures, Exper. Math. 20 (2) (2011) 145-152` `Durhuus and S. Eilers, On the entropy of LEGO, arXiv:math.CO/0504039`
	CROSSREFS	`Sequence in context: A186132 A206504 A046172 * A115443 A328089 A186527` `Adjacent sequences: A123844 A123845 A123846 * A123848 A123849 A123850`
	KEYWORD	`nonn,hard`
	AUTHOR	`Søren Eilers, Oct 29 2006`
	STATUS	`approved`

Last modified May 26 00:47 EDT 2022. Contains 354073 sequences. (Running on oeis4.)