Title
Union-closed families of sets
Abstract
A family of sets is union-closed if it contains the union of any two of its elements. Reimer (2003) [16] and Czedli (2009) [2] investigated the average size of an element of a union-closed family consisting of m subsets of a ground set with n elements. We determine the minimum average size precisely, verifying a conjecture of Czedli, Maroti and Schmidt (2009) [3]. As a consequence, the union-closed conjecture holds if m=23.2^n - in this case some element of [n] is in at least half the sets of the family.
Year
DOI
Venue
2013
10.1016/j.jcta.2012.10.005
J. Comb. Theory, Ser. A
Keywords
Field
DocType
m subsets,union-closed family,minimum average size,average size,n element,union-closed conjecture
Discrete mathematics,Family of sets,Combinatorics,Conjecture,Mathematics
Journal
Volume
Issue
ISSN
120
3
0097-3165
Citations 
PageRank 
References 
5
0.50
12
Authors
3
Name
Order
Citations
PageRank
Igor Balla151.85
Béla Bollobás22696474.16
Tom Eccles3175.77