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A030269 Number of nonisomorphic disconnected partial lattices. 0
0, 0, 1, 2, 6, 18, 69, 287, 1397, 7634, 46972, 321014, 2416305, 19840547, 176267022, 1681915809, 17127587977, 185127766583 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

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.

LINKS

Table of n, a(n) for n=0..17.

CROSSREFS

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

Sequence in context: A150081 A006674 A006389 * A150082 A177470 A060181

Adjacent sequences:  A030266 A030267 A030268 * A030270 A030271 A030272

KEYWORD

nonn,hard

AUTHOR

Christian G. Bower, revised Dec 28 2000

STATUS

approved

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Last modified April 4 05:34 EDT 2020. Contains 333212 sequences. (Running on oeis4.)