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                * Princeton Discrete Math Seminar *
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Date: Thursday 10th November, 3:00 in Fine Hall 224.
 
Speaker: Oliver Schaudt (Köln)

Title: The union-closed sets conjecture.

The union-closed sets conjecture is an elementary problem posed by Frankl 
in 1979. It goes like this: for any finite family of finite sets, closed
under taking union, there exists an element that belongs to at least half 
of the sets in the family. This problem attracted recent interest for
being a polymath project.

I will explain important partial results and discuss a graph-theoretic  
reformulation of the conjecture.

Based on joint work with Henning Bruhn, Jan-Arne Telle and Pierre Charbit.

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Next week: Patrick Devlin

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