A030269 Number of nonisomorphic disconnected partial lattices.

0, 0, 1, 2, 6, 18, 69, 287, 1397, 7634, 46972, 321014, 2416305, 19840547, 176267022, 1681915809, 17127587977, 185127766583

Offset: 0

Author

Christian G. Bower, revised Dec 28 2000

Keywords

• nonn
• hard

Comments

A partial lattice is a poset where every pair of points has a unique least upper (greatest lower) bound or has no upper (lower) bound.

Crossrefs

a(n) = A006966(n-2) - A030268(n).