A229202 Number of semimodular lattices on n nodes.

1, 1, 1, 1, 2, 4, 8, 17, 38, 88, 212, 530, 1376, 3693, 10232, 29231, 85906, 259291, 802308, 2540635, 8220218, 27134483, 91258141, 312324027, 1086545705, 3838581926

Offset

0,5

Links

Table of n, a(n) for n=0..25.

P. Jipsen and N. Lawless, Generating all modular lattices of a given size

J. Kohonen, Generating modular lattices up to 30 elements, arXiv:1708.03750 [math.CO] preprint (2017).

Crossrefs

Cf. A006966 (number of lattices), A006981 (number of modular lattices).

Sequence in context: A025276 A006461 A257300 * A003007 A086615 A357903

Adjacent sequences: A229199 A229200 A229201 * A229203 A229204 A229205

Keyword

nonn,more

Author

Nathan Lawless, Sep 15 2013

Extensions

a(23)-a(25) from Kohonen (2017), by Jukka Kohonen, Aug 15 2017

Status

approved