Abstract
A pair of families (F, G) is said to be cross-Sperner if there exists no pair of sets F F, G G with F G or G F. There are two ways to measure the size of the pair (F, G): with the sum |F| + |G| or with the product |F| • |G|. We show that if F, G 2[n], then |F| |G| 22n-4 and |F| + |G| is maximal if F or G consists of exactly one set of size 2 provided the size of the ground set n is large enough and both F and G are nonempty.
Original language | English |
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Pages (from-to) | 44-51 |
Number of pages | 8 |
Journal | Studia Scientiarum Mathematicarum Hungarica |
Volume | 49 |
Issue number | 1 |
DOIs | |
State | Published - Mar 1 2012 |
Keywords
- Extremal set systems
- Primary 05D05
- Sperner property