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A361959
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Number of connected unlabeled tiered posets with n elements.
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3
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1, 1, 1, 3, 8, 25, 83, 330, 1538, 8834, 63723, 591313, 7180087, 115411088, 2472336977, 70840464484, 2720170935989, 140167035897433, 9702508891845883, 903305670556552694, 113233954374954246849, 19137449587197829494989, 4366006746295284220605007
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OFFSET
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0,4
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COMMENTS
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A tiered poset is a partially ordered set in which every maximal chain has the same length.
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LINKS
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PROG
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(PARI) \\ See PARI link in A361957 for program code.
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CROSSREFS
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Cf. A361912 (not necessarily connected).
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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