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A361959
Number of connected unlabeled tiered posets with n elements.
3
1, 1, 1, 3, 8, 25, 83, 330, 1538, 8834, 63723, 591313, 7180087, 115411088, 2472336977, 70840464484, 2720170935989, 140167035897433, 9702508891845883, 903305670556552694, 113233954374954246849, 19137449587197829494989, 4366006746295284220605007
OFFSET
0,4
COMMENTS
A tiered poset is a partially ordered set in which every maximal chain has the same length.
LINKS
PROG
(PARI) \\ See PARI link in A361957 for program code.
A361959seq(20) \\ Andrew Howroyd, Apr 03 2023
CROSSREFS
Row sums of A361958.
Cf. A361912 (not necessarily connected).
Sequence in context: A148797 A123638 A207651 * A038665 A172382 A151426
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Apr 03 2023
STATUS
approved