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A058793
Number of covers of an unlabeled n-set such that every point of the set is covered by exactly 6 subsets of the cover and that intersection of every 6 subsets of the cover contains at most one point.
1
1, 6, 73, 2957, 431805, 193413963, 198914729182, 389238347659505, 1292594846197639190, 6753309741099683530616
OFFSET
1,2
COMMENTS
Cover may include multiple occurrences of a subset. Also n-rowed binary matrices with distinct rows and all row sums 6.
LINKS
CROSSREFS
Row n=6 of A331508.
Sequence in context: A346960 A168603 A244689 * A066171 A269647 A232330
KEYWORD
more,nonn
AUTHOR
Vladeta Jovovic, Nov 30 2000
EXTENSIONS
a(6)-a(10) from Andrew Howroyd, Jan 29 2020
STATUS
approved