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A358710
Triangle read by rows. Number T(n, k) of partitions of the multiset [1, 1, 2, 2, ..., n, n] into k nonempty submultisets, for 1 <= k <= 2n.
3
1, 1, 1, 1, 4, 3, 1, 1, 13, 26, 19, 6, 1, 1, 40, 183, 259, 163, 55, 10, 1, 1, 121, 1190, 3115, 3373, 1896, 620, 125, 15, 1, 1, 364, 7443, 34891, 62240, 54774, 27610, 8706, 1795, 245, 21, 1, 1, 1093, 45626, 374059, 1072316, 1435175, 1063570, 485850, 146363, 30261, 4361, 434, 28, 1
OFFSET
0,5
COMMENTS
A generalization of ordinary Stirling set numbers to multisets that contain some m instances each of n elements, here we have m=2.
REFERENCES
F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
EXAMPLE
The triangular array starts:
[0] 1;
[1] 1, 1;
[2] 1, 4, 3, 1;
[3] 1, 13, 26, 19, 6, 1;
[4] 1, 40, 183, 259, 163, 55, 10, 1;
[5] 1, 121, 1190, 3115, 3373, 1896, 620, 125, 15, 1;
[6] 1, 364, 7443, 34891, 62240, 54774, 27610, 8706, 1795, 245, 21, 1;
CROSSREFS
Cf. A008277, A020555 (row sums), A358721, A358722.
Sequence in context: A189967 A139623 A278072 * A216482 A080758 A123683
KEYWORD
nonn,tabf
AUTHOR
Marko Riedel, Nov 27 2022
STATUS
approved