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A058801
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Number of connected vertically indecomposable partial lattices on n unlabeled nodes.
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0
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1, 2, 6, 25, 116, 625, 3757, 25140, 184511, 1473861, 12711339, 117598686, 1160399052, 12152333659, 134487937252, 1566878426731, 19154490559458
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OFFSET
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2,2
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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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FORMULA
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Inverse EULER transform of A058800(n+2).
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MATHEMATICA
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A058800 = Cases[Import["https://oeis.org/A058800/b058800.txt", "Table"], {_, _}][[All, 2]];
(* EulerInvTransform is defined in A022562 *)
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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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EXTENSIONS
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STATUS
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approved
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