OFFSET
0,10
COMMENTS
The sum of the m-th row is the (m-1)-st member of A033995, number of bipartite graphs with n nodes.
REFERENCES
F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, New York / London, 1973.
LINKS
P. Hanlon, The enumeration of bipartite graphs, Discrete Math. 28 (1979), 49-57.
Juergen Will, Rows 0 to 10 of triangle.
EXAMPLE
Triangle begins:
0: 1;
1: 1;
2: 1, 1;
3: 1, 1, 1;
4: 1, 1, 2, 2, 1;
5: 1, 1, 2, 3, 4, 1, 1;
6: 1, 1, 2, 4, 7, 8, 6, 3, 2, 1;
7: 1, 1, 2, 4, 8, 13, 19, 14, 13, 7, 4, 1, 1;
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Juergen Will, Jan 07 2018
STATUS
approved