Séminaire Lotharingien de Combinatoire, B69pref (2012), 1 p.

Christian Krattenthaler


The 69th Meeting of the Séminaire Lotharingien de Combinatoire took place from September 9 to 12, 2012, in the Bundesinstitut für Erwachsenenbildung in Strobl (Austria). This was the third time that the Séminaire was held here.

This time we had the pleasure to be introduced to the elegant theory of stable functions by Petter Brändén who gave us a series of lectures on "Zeros of Multivariate Polynomials in Combinatorics". The second series of lectures, "Cluster Algebras and Lie Theory", was given by Bernard Leclerc, who presented us a very motivated introduction to Fomin and Zelevinsky's cluster algebras, followed by a survey of recent results of his and co-authors, lending deep insight into the structure of cluster algebras related to Lie theory, including a glimpse of categorification.

Several of the contributed talks (see the detailed list below) connected to the main lectures in that they addressed combinatorial questions related to (finite) Coxeter groups or zeroes of combinatorial polynomials. Other talks concerned combinatorial Hopf algebras, orthogonal polynomials, and problems of enumeration.

Weather stuck precisely to the forecast, which meant that the participants could enjoy swimming in the lake on Monday and Tuesday, and typical (rainy) Salzkammergut weather on Wednesday ... In summary, this was another very enjoyable Séminaire, with very interesting, productive discussions.

Contributed talks:

Olga AZENHAS: Key polynomials in type C and crystal graphs

Adam BOHN: On the question on which algebraic integers are chromatic roots

Gérard DUCHAMP: Fuchsian-type multipliers and shuffle algebras

Matthieu JOSUAT-VERGÈS: A Coxeter theoretic interpretation of Euler numbers

Myrto KALLIPOLITI: Integer partition models for extended Catalan arrangements and generalized cluster complexes

Anisse KASRAOUI: Difference equations and linearization of a product of orthogonal polynomials

Bodo LASS: Mehler formulae for multivariate matching polynomials of graphs

Henri MÜHLE: The Cambrian lattices are EL-shellable

Philippe NADEAU: Dual braid monoids and Koszulity

Nguyen HOANG-NGHIA: A word Hopf algebra based on the selection/quotient principle

Eric NORDENSTAM: Tilings of half a hexagon

Leandro VENDRAMIN: Nichols algebras

Mirkó VISONTAI: Roots of generalized Eulerian polynomials arising from inversion sequences

List of Participants: