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                * Princeton Discrete Math Seminar *
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Date: Thursday 3rd December, 3:00 in Fine Hall 224.
 
Speaker: Peter Winkler (Dartmouth)

Title: Permutons

What do permutations of 1 through n, for large n, look like?  For example, 
how can we generate a random permutation that inverts a third of its pairs?  
How many such permutations are there?
   
Permutons are doubly-stochastic measures; they are exactly the limit
objects for large permutations, in the appropriate topology.  By finding
permutons that maximize entropy, we (with Rick Kenyon, Dan Kral and 
Charles Radin) are able in some cases to count and describe permutations 
with specified pattern densities.  We'll show how permutons arise in several
situations, and try to explain why they work, in some respects, better than
graphons do for graphs.

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Next week: Adam Marcus

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