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A342590
T(n,k) is the number of connected posets of n unlabeled elements with k covering relations (n>=1, k>=0). Triangle read by rows.
4
1, 0, 1, 0, 0, 3, 0, 0, 0, 8, 2, 0, 0, 0, 0, 27, 12, 5, 0, 0, 0, 0, 0, 91, 87, 45, 12, 3, 0, 0, 0, 0, 0, 0, 350, 532, 475, 201, 71, 14, 7, 0, 0, 0, 0, 0, 0, 0, 1376, 3272, 4298, 3197, 1565, 554, 186, 44, 16, 4, 0, 0, 0, 0, 0, 0, 0, 0, 5743, 19396, 36664, 41706, 31931, 16972
OFFSET
1,6
EXAMPLE
The table starts
1: 1
2: 0 1
3: 0 0 3
4: 0 0 0 8 2
5: 0 0 0 0 27 12 5
6: 0 0 0 0 0 91 87 45 12 3
7: 0 0 0 0 0 0 350 532 475 201 71 14 7
8: 0 0 0 0 0 0 0 1376 3272 4298 3197 1565 554 186 44 16 4
CROSSREFS
Cf. A000608 (row sums), A022017 (column sums), A342447 (not necess. connected), A342588 (labeled).
Sequence in context: A344976 A344876 A129170 * A209436 A229121 A190609
KEYWORD
nonn,tabf
AUTHOR
R. J. Mathar, Mar 16 2021
STATUS
approved