A000513 - cp's OEIS frontend

A000513 Number of equivalence classes of n X n matrices over {0,1} with rows and columns summing to 4, where equivalence is defined by row and column permutations. Also number of isomorphism classes of bicolored quartic bipartite graphs, where isomorphism cannot exchange the colors.

n	a(n)
1	0
2	0
3	0
4	1
5	1
6	4
7	16
8	194
9	3529
10	121790
11	5582612
12	317579783
13	21543414506
14	1711281449485
15	157117486414656
16	16502328443493967
17	1965612709107379155
18	263512349078757245789
19	39497131936385398782814
20	6579940884199010139737829
21	1211896874083479131415289345
22	245593008009270037388205883048

[0, 0, 0, 1, 1, 4, 16, 194, 3529, 121790, 5582612, 317579783, 21543414506, 1711281449485, 157117486414656, 16502328443493967, 1965612709107379155, 263512349078757245789, 39497131936385398782814, 6579940884199010139737829, 1211896874083479131415289345, 245593008009270037388205883048]

cp's OEIS Frontend

A000513 Number of equivalence classes of n X n matrices over {0,1} with rows and columns summing to 4, where equivalence is defined by row and column permutations. Also number of isomorphism classes of bicolored quartic bipartite graphs, where isomorphism cannot exchange the colors.

Table of values

List of values