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                * Princeton Discrete Math Seminar *
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Date: Thursday 6th December, 2.00 in Fine Hall 224
 
Speaker:  David Pritchard, Princeton.

Title: Cover-decomposition and polychromatic numbers

In the cover-decomposition problem we are given a ground set of points
and a collection of its subsets. Suppose that we want to colour some
subsets blue and the others red, so that every point lies in both a
blue subset and a red subset. An obvious necessary condition is that
every point lies in at least two subsets; is there an exact or
approximate converse? What about when there are many colours? Using
probabilistic methods and iterated linear programming we'll give
positive answers in some settings.

This is joint work with Bela Bollobas, Thomas Rothvoss and Alex Scott.

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Next week: TBA

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