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                * Princeton Discrete Math Seminar *
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Speaker: Miklos Bona, University of Florida

Thursday 6th February, 3:00 in Fine Hall 224.

Title: A method to prove that the solution to some enumeration problems is a 
non-rational generating function.

The solution of an enumeration problem is very often a generating 
function F. Some problems are too difficult for  us to find the explicit 
form of F. In this talk, we will introduce a method that leads to negative 
results that are rare in this part of combinatorics. When our method applies, 
it shows that F is not a rational function, which provides at least some 
explanation of the fact that the original enumeration problem is difficult. 
As an example, we will discuss a 22-year old conjecture of Zeilberger and 
Noonan.

The talk will be accessible to graduate students.

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Next week: Ander Lamaison

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