Title
All maximum 2-part Sperner families
Abstract
Let X = X 1 ∪ X 2 , X 1 ∩ X 2 = 0 be a partition of an n -element set. Suppose that the family F of some subsets of X satisfy the following condition: if there is an inclusion F 1 ⊈ F 2 ( F 1 , F 2 ϵ F ) in F , the difference F 2 − F 1 cannot be a subset of X 1 or X 2 . Kleitman ( Math. Z. 90 (1965), 251–259) and Katona ( Studia Sci. Math. Hungar. 1 (1966), 59–63) proved 20 years ago that | F | is at most n choose  n 2  . We determine all families giving equality in this theorem.
Year
DOI
Venue
1986
10.1016/0097-3165(86)90023-3
J. Comb. Theory, Ser. A
Keywords
DocType
Volume
2-part sperner family
Journal
43
Issue
ISSN
Citations 
1
Journal of Combinatorial Theory, Series A
8
PageRank 
References 
Authors
1.21
1
1
Name
Order
Citations
PageRank
PETER L.181.21