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A263863
Triangle read by rows: T(n,k) (n>=0, k>=n+1) is the number of posets with n elements and k chains.
0
1, 1, 1, 1, 1, 1, 2, 0, 1, 1, 1, 3, 3, 2, 2, 0, 3, 0, 0, 0, 1, 1, 1, 3, 5, 8, 5, 7, 4, 8, 2, 5, 1, 5, 0, 3, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
0,7
COMMENTS
Row sums give A000112.
LINKS
FindStat - Combinatorial Statistic Finder, The number of chains of a poset.
EXAMPLE
Triangle begins:
1,
1,
1,1,
1,1,2,0,1,
1,1,3,3,2,2,0,3,0,0,0,1,
1,1,3,5,8,5,7,4,8,2,5,1,5,0,3,0,0,0,4,0,0,0,0,0,0,0,1,
...
CROSSREFS
Cf. A000112.
Sequence in context: A254045 A024996 A187596 * A134655 A262124 A199954
KEYWORD
nonn,tabf
AUTHOR
Christian Stump, Oct 28 2015
STATUS
approved