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Related papers: Schroder combinatorics and $\nu$-associahedra

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We give a combinatorial expansion of the stable Grothendieck polynomials of skew Young diagrams in terms of skew Schur functions, using a new row insertion algorithm for set-valued semistandard tableaux of skew shape. This expansion unifies…

Combinatorics · Mathematics 2020-09-15 Melody Chan , Nathan Pflueger

We study character varieties arising as moduli of representations of an orientable surface group into a reductive group $G$. We first show that if $G/Z$ acts freely on the representation variety, then both the representation variety and the…

Representation Theory · Mathematics 2025-02-12 Masoud Kamgarpour , GyeongHyeon Nam , Anna Puskás

We establish a poset structure on combinatorial bases of multivariate polynomials defined by positive expansions, and study properties common to bases in this poset. Included are the well-studied bases of Schubert polynomials, Demazure…

Combinatorics · Mathematics 2018-08-09 Dominic Searles

We define a number of related combinatorial objects, each of which possesses a surprising symmetry. We include several applications such as a combinatorial explanation for certain fixed points of the involution $\omega$ on the ring of…

Combinatorics · Mathematics 2018-09-13 Graham Hawkes

The product $s_\mu s_\nu$ of two Schur functions is one of the most famous examples of a Schur-positive function, i.e. a symmetric function which, when written as a linear combination of Schur functions, has all positive coefficients. We…

Combinatorics · Mathematics 2007-05-23 Francois Bergeron , Peter McNamara

Much of modern Schubert calculus is centered on Schubert varieties in the complete flag variety and on their classes in its integral cohomology ring. Under the Borel isomorphism, these classes are represented by distinguished polynomials…

Combinatorics · Mathematics 2025-09-05 Laura Escobar , Patricia Klein , Anna Weigandt

We give new interpretations of the $\nu$-Tamari lattice of Pr\'eville-Ratelle and Viennot. First, we describe it as a rotation lattice of $\nu$-trees, which uncovers the relation with known combinatorial objects such as tree-like tableaux…

Combinatorics · Mathematics 2019-10-08 Cesar Ceballos , Arnau Padrol , Camilo Sarmiento

We compute the expansion of the cohomology class of the permutahedral variety in the basis of Schubert classes. The resulting structure constants $a_w$ are expressed as a sum of \emph{normalized} mixed Eulerian numbers indexed naturally by…

Combinatorics · Mathematics 2023-06-22 Philippe Nadeau , Vasu Tewari

This paper introduces the geometric foundations for the study of the $s$-permutahedron and the $s$-associahedron, two objects that encode the underlying geometric structure of the $s$-weak order and the $s$-Tamari lattice. We introduce the…

Combinatorics · Mathematics 2025-02-26 Cesar Ceballos , Viviane Pons

The purpose of this work is to give a first approach to the dynamical behavior of Schr\"oder's method, a well known iterative process for solving nonlinear equations. In this context we consider equations defined in the complex plane. By…

Dynamical Systems · Mathematics 2020-11-30 José M. Gutiérrez , Víctor Galilea

We study some distributive lattices arising in the combinatorics of lattice paths. In particular, for the Dyck, Motzkin and Schroder lattices we describe the spectrum and we determine explicitly the Euler characteristic in terms of natural…

Combinatorics · Mathematics 2009-05-26 Luca Ferrari , Emanuele Munarini

I present an overview of the research I have conducted for the past ten years in algebraic, bijective, enumerative, and geometric combinatorics. The two main objects I have studied are the permutahedron and the associahedron as well as the…

Combinatorics · Mathematics 2023-10-20 Viviane Pons

For each poset $P$, we construct a polytope $A(P)$ called the $P$-associahedron. Similarly to the case of graph associahedra, the faces of $A(P)$ correspond to certain nested collections of subsets of $P$. The Stasheff associahedron is a…

Combinatorics · Mathematics 2023-11-09 Pavel Galashin

In the early 1990's, Billera and Sturmfels introduced the monotone path polytope (MPP), a special case of the general theory of fiber polytopes that associates a polytope to a pair $(P,\varphi)$ of a polytope $P$ and linear functional…

Combinatorics · Mathematics 2021-04-16 Alexander Black , Jesús De Loera

We study the asymptotics of Schur polynomials with partitions $\lambda$ which are almost staircase; more precisely, partitions that differ from $((m-1)(N-1),(m-1)(N-2),\ldots,(m-1),0)$ by at most one component at the beginning as…

Probability · Mathematics 2020-09-01 Zhongyang Li

We study the problem (-\epsilon\mathrm{i}\nabla+A(x)) ^{2}u+V(x)u=\epsilon ^{-2}(\frac{1}{|x|}\ast|u|^{2}) u, u\in L^{2}(\mathbb{R}^{3},\mathbb{C}),\text{\ \ \ \}\epsilon\nabla u+\mathrm{i}Au\in L^{2}(\mathbb{R}^{3},\mathbb{C}^{3}), where…

Analysis of PDEs · Mathematics 2011-10-21 Silvia Cingolani , Mónica Clapp , Simone Secchi

The Kronecker product of two Schur functions $s_{\mu}$ and $s_{\nu}$, denoted by $s_{\mu}*s_{\nu}$, is the Frobenius characteristic of the tensor product of the irreducible representations of the symmetric group corresponding to the…

Combinatorics · Mathematics 2007-05-23 Mercedes H. Rosas

In this paper the one-dimensional nonparaxial nonlinear Schr\"odinger equation is considered. This was proposed as an alternative to the classical nonlinear Schr\"odinger equation in those situations where the assumption of paraxiality may…

Analysis of PDEs · Mathematics 2019-02-25 B. Cano , A. Durán

This paper is motivated by two problems recently proposed by Coker on combinatorial identities related to the Narayana polynomials and the Catalan numbers. We find that a bijection of Chen, Deutsch and Elizalde can be used to provide…

Combinatorics · Mathematics 2007-05-23 William Y. C. Chen , Sherry H. F. Yan , Laura L. M. Yang

We describe a bijection between $(k,k)$-Fuss-Schr\"oder paths of type $\lambda$ and certain rooted plane forests with $n(k+1)+2$ vertices. This yields a recursion which allows us to analytically enumerate the number of large…

Combinatorics · Mathematics 2018-05-15 Michael Kural