A123825 - OEIS

This site is supported by donations to The OEIS Foundation.

A123825

Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 2x3 which is symmetric after a rotation by 180 degrees.

1, 1, 25, 53, 1189, 2947, 66094, 181955, 3979943 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,3`
	REFERENCES	`M. Abrahamsen and S. Eilers, Efficient counting of LEGO buildings, in preparation` `B. Durhuus and S. Eilers, On the entropy of LEGO, arXiv:math.CO/0504039`
	LINKS	`S. Eilers, LEGO counts`
	CROSSREFS	`Sequence in context: A118304 A117472 A146633 * A157269 A186892 A206075` `Adjacent sequences: A123822 A123823 A123824 * A123826 A123827 A123828`
	KEYWORD	`nonn`
	AUTHOR	`Soren Eilers (eilers(AT)math.ku.dk), Oct 29 2006`

Content is available under The OEIS End-User License Agreement .

Last modified February 15 23:53 EST 2012. Contains 205860 sequences.