A058791 - cp's OEIS frontend

A058791 Number of covers of an unlabeled n-set such that every point of the set is covered by exactly 4 subsets of the cover and that intersection of every 4 subsets of the cover contains at most one point.

n	a(n)
1	1
2	4
3	25
4	278
5	5532
6	200589
7	11662671
8	981458725
9	111213730857
10	16212510876591
11	2947663429595884
12	653299790376494253
13	173373367472722467460
14	54295204354760461199529
15	19822683467350158062736540

[1, 4, 25, 278, 5532, 200589, 11662671, 981458725, 111213730857, 16212510876591, 2947663429595884, 653299790376494253, 173373367472722467460, 54295204354760461199529, 19822683467350158062736540]

cp's OEIS Frontend

A058791 Number of covers of an unlabeled n-set such that every point of the set is covered by exactly 4 subsets of the cover and that intersection of every 4 subsets of the cover contains at most one point.

Table of values

List of values