The main lectures were given by **Guo-Niu Han** (Strasbourg)
and **Igor Pak** (Los Angeles). Guo-Niu Han reported on his
*"Recent Work on Hankel
Determinants"*, showing us techniques for proving non-vanishing
and/or periodicity of Hankel determinants which arise from the
study of irrationality measures in number theory. Igor Pak on
the other hand, in his series of lectures
*"New Foundations of
Combinatorial Theory"*, presented us three beautiful
selections from recent work of his, covering a wide variety of
topics ranging from the use of tilings to generate integer
sequences, partitions, Kronecker coefficients, up to
counting integer points in polytopes, including of course
his love, bijections, and he interspersed this with
excursions of more "philosophical" nature, where he
set out his view of the key
words in the titles of his three lectures.

The contributed talks (see the detailed list below) covered also various topics, including the combinatorics of Coxeter groups, Kazhdan-Lusztig polynomials, Jack polynomials, Kostka numbers, partitions, and related polytopes, Kronecker coefficients, Schubert calculus, parking functions, permutations, and some conjectures by Atiyah in "elementary" geometry, which do not seem so "easy" to prove after all ...

Although weather forecast was not very promising, it turned out to be perfect for taking swims in the lake or hikes in the neighbourhood during the lunch breaks (with showers occurring only during the night and during lectures). In summary, this was another very pleasant Séminaire, with a lively exchange of ideas and fruitful discussions. It deserves special mention that this session of the Séminaire saw a record participation from the Lotharingian division in the Far East, with 5 participants from Japan.

**Mathilde BOUVEL**: *A general theory of Wilf-equivalence for Catalan
structures*

**Felix BREUER**: *The geometry of the restricted partition function, I*

**Laura COLMENAREJO**: *Stability of plethysm coefficients*

**Angela CARNEVALE**: *A proof of two conjectures by B. Klopsch, A. Stasinski and C. Voll*

**Valentin FÉRAY**: *Shifted Jack polynomials and multirectangular coordinates*

**Antonio GUEDES DE OLIVEIRA**: *The braid and the Shi arrangements and the
Pak-Stanley labelling*

**Masao ISHIKAWA**: *Selberg integrals and evaluations of Pfaffians*

**Brandt KRONHOLM**: *The geometry of the restricted partition function, II*

**Hiroshi NARUSE**: *Schubert calculus and hook formula*

**Soichi OKADA**: *Pfaffian formulae and their applications to symmetric function
identities*

**Mathias PÉTRÉOLLE**: *A Nekrasov-Okounkov formula in type C*

**Vivien RIPOLL**: *Coxeter elements in well-generated reflection groups*

**Paolo SENTINELLI**: *Complements of Coxeter group quotients*

**Dragutin SVRTAN**: *A proof of all three Euclidian four-point Atiyah-Sutcliffe conjectures*

- Per Alexandersson (Zürich)
- Olga Azenhas (Coimbra)
- Sabine Beil (Wien)
- Riccardo Biagioli (Lyon)
- Mathilde Bouvel (Zürich)
- Francesco Brenti (Roma)
- Felix Breuer (Linz)
- Angela Carnevale (Roma)
- Laura Colmenarejo (Sevilla)
- Theresia Eisenkölbl (Lyon)
- Valentin Féray (Zürich)
- António Guedes de Oliveira (Porto)
- Guo-Niu Han (Strasbourg)
- Frédéric Jouhet (Lyon)
- Christian Krattenthaler (Wien)
- Brandt Kronholm (Linz)
- Bodo Lass (Lyon)
- Ricardo Mamede (Coimbra)
- Philippe Nadeau (Lyon)
- Hiroshi Naruse (Okayama)
- Soichi Okada (Nagoya)
- Igor Pak (Los Angeles)
- Mathias Pétréolle (Lyon)
- Vivien Ripoll (Wien)
- Taizo Sadahiro (Tokyo)
- Paolo Sentinelli (Roma)
- Dario De Stavola (Zürich)
- Robin Sulzgruber (Wien)
- Dragutin Svrtan (Zagreb)
- Volker Strehl (Erlangen)
- Itaru Terada (Tokyo)
- Marko Thiel (Wien)
- Jiang Zeng (Lyon)