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.
LINKS
Sidney Cadot, Table of n, a(n) for n = 0..420 (terms 1..420 from Marko Riedel)
Marko Riedel et al., Number of ways to partition a multiset into k non-empty multisets, Mathematics Stack Exchange.
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
KEYWORD
nonn,tabf
AUTHOR
Marko Riedel, Nov 27 2022
STATUS
approved