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Related papers: Schur positivity and Schur log-concavity

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We introduce the antipodal pairs property for probability measures on finite Boolean algebras and prove that conditional versions imply strong forms of log-concavity. We give several applications of this fact, including improvements of some…

Combinatorics · Mathematics 2009-07-03 Jeff Kahn , Michael Neiman

We present positivity conjectures for the Schur expansion of Jack symmetric functions in two bases given by binomial coefficients. Partial results suggest that there are rich combinatorics to be found in these bases, including Eulerian…

Combinatorics · Mathematics 2019-07-02 Per Alexandersson , James Haglund , George Wang

We prove a conjecture by Shannon Starr regarding the asymptotics for the number of tuples of commuting permutations with given number of joint orbits. These numbers generalize unsigned Stirling numbers of the first kind which count how many…

Combinatorics · Mathematics 2025-06-10 Abdelmalek Abdesselam

We apply a theorem of Geronimus to derive some new formulas connecting Schur functions with orthogonal polynomials on the unit circle. The applications include the description of the associated measures and a short proof of Boyd's result…

Classical Analysis and ODEs · Mathematics 2009-09-25 Feruenc Pinteŕ , Paul G. Nevai

In previous work with Mikhail Khovanov and Aaron Lauda we introduced two odd analogues of the Schur functions: one via the combinatorics of Young tableaux (odd Kostka numbers) and one via the odd symmetrization operator. In this paper we…

Quantum Algebra · Mathematics 2011-11-17 Alexander P. Ellis

Assuming the existence of Siegel zeros, we prove that there exists an increasing sequence of positive integers for which Chowla's Conjecture on $k$-point correlations of the Liouville function holds. This extends work of Germ\'an and…

Number Theory · Mathematics 2021-06-01 Jake Chinis

We introduce non-commutative analogues of $k$-Schur functions of Lapointe-Lascoux and Morse. We give an explicit formulas for the expansions of non-commutive functions with one and two parameters in terms of these new functions. These…

Combinatorics · Mathematics 2016-11-08 N. Bergeron , F. Descouens , M. Zabrocki

We discuss several well known results about Schur functions that can be proved using cancellations in alternating summations; notably we shall discuss the Pieri and Murnaghan-Nakayama rules, the Jacobi-Trudi identity and its dual (Von…

Combinatorics · Mathematics 2007-05-23 Marc A. A. van Leeuwen

We prove that a conjecture of Fomin, Fulton, Li, and Poon, associated to ordered pairs of partitions, holds for many infinite families of such pairs. We also show that the bounded height case can be reduced to checking that the conjecture…

Combinatorics · Mathematics 2009-09-29 Francois Bergeron , Riccardo Biagioli , Mercedes H. Rosas

In this paper, we extend recent results of Assaf and McNamara on skew Pieri rule and skew Murnaghan-Nakayama rule to a more general identity, which gives an elegant expansion of the product of a skew Schur function with a quantum power sum…

Combinatorics · Mathematics 2011-01-28 Matjaz Konvalinka

We determine the precise conditions under which any skew Schur function is equal to a Schur function over both infinitely and finitely many variables.

Combinatorics · Mathematics 2007-06-22 Stephanie van Willigenburg

We give a combinatorial proof that the product of a Schubert polynomial by a Schur polynomial is a nonnegative sum of Schubert polynomials. Our proof uses Assaf's theory of dual equivalence to show that a quasisymmetric function of Bergeron…

Combinatorics · Mathematics 2014-05-13 Sami Assaf , Nantel Bergeron , Frank Sottile

We prove that the set of matchings with a fixed number of unmatched vertices is Schur-positive with respect to the set of short chords. Two proofs are presented. The first proof applies a new combinatorial criterion for Schur-positivity,…

Combinatorics · Mathematics 2026-05-21 Avichai Marmor

We define a new family of symmetric functions which are affine analogues of Stanley symmetric functions. We establish basic properties of these functions including symmetry, dominance and conjugation. We conjecture certain positivity…

Combinatorics · Mathematics 2007-05-23 Thomas Lam

We introduce a notion of {\em cyclic Schur-positivity} for sets of permutations, which naturally extends the classical notion of Schur-positivity, and it involves the existence of a bijection from permutations to standard Young tableaux…

Combinatorics · Mathematics 2019-08-22 Jonathan Bloom , Sergi Elizalde , Yuval Roichman

We prove a conjecture of Liu and Wang on the q-log-convexity of the polynomial sequence $\{\sum_{k=0}^n{n\choose k}^2q^k\}_{n\geq 0}$. By using Pieri's rule and the Jacobi-Trudi identity for Schur functions, we obtain an expansion of a sum…

Combinatorics · Mathematics 2008-10-14 William Y. C. Chen , Robert L. Tang , Larry X. W. Wang , Arthur L. B. Yang

We obtain the Schur positivity of spider graphs of the forms $S(a,2,1)$ and $S(a,4,1)$, which are considered to have the simpliest structures for which the Schur positivity was unknown. The proof outline has four steps. First, we find…

Combinatorics · Mathematics 2023-05-16 Jean-Yves Thibon , David G. L. Wang

Let $\Lambda$ be the space of symmetric functions and $V_k$ be the subspace spanned by the modified Schur functions $\{S_\lambda[X/(1-t)]\}_{\lambda_1\leq k}$. We introduce a new family of symmetric polynomials,…

Quantum Algebra · Mathematics 2007-05-23 L. Lapointe , A. Lascoux , J. Morse

We develop the theory of Schur covers of finite skew braces. We prove the existence of at least one Schur cover. We also compute several examples. We prove that different Schur covers are isoclinic. Finally, we prove that Schur covers have…

Group Theory · Mathematics 2024-02-01 T. Letourmy , L. Vendramin

We prove Stanley's conjecture that, if delta_n is the staircase shape, then the skew Schur functions s_{delta_n / mu} are non-negative sums of Schur P-functions. We prove that the coefficients in this sum count certain fillings of shifted…

Combinatorics · Mathematics 2011-08-11 Federico Ardila , Luis G. Serrano