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A030269
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Number of nonisomorphic disconnected partial lattices.
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0
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0, 0, 1, 2, 6, 18, 69, 287, 1397, 7634, 46972, 321014, 2416305, 19840547, 176267022, 1681915809, 17127587977, 185127766583
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OFFSET
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0,4
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COMMENTS
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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.
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LINKS
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CROSSREFS
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KEYWORD
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nonn,hard
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AUTHOR
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STATUS
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approved
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