Refined Ehrhart polynomials and an h*-triangle

Algebraic and Enumerative Combinatorics

12 March 11:00 - 11:50


: I will discuss some current work with Florian Kohl on a refinement of the Ehrhart polynomial of a polytope: ehr(s,t). For the corresponding generating function, we get a triangle of h*-coefficients instead of a vector and we prove that they are non-negative. Sometimes both s=1 and s=2 turns the refined Ehrhart polynomial into an ordinary one, as for example for stable set polytopes of perfect graphs and their associated reflexive polytopes. We state some conjectures on the h*-triangle.
Sara Billey
University of Washington
Petter Brändén
KTH Royal Institute of Technology
Sylvie Corteel
Université Paris Diderot, Paris 7
Svante Linusson
KTH Royal Institute of Technology


Svante Linusson


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