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The P-Eulerian polynomial counts the linear extensions of a labeled partially ordered set, P, by their number of descents. It is known that the P-Eulerian polynomials are real-rooted for various classes of posets P. The purpose of this…

Combinatorics · Mathematics 2016-04-15 Petter Brändén , Madeleine Leander

The Eulerian polynomials enumerate permutations according to their number of descents. We initiate the study of descent polynomials over Cayley permutations, which we call Caylerian polynomials. Some classical results are generalized by…

Combinatorics · Mathematics 2024-07-17 Giulio Cerbai , Anders Claesson

We define a new family of generalized Stirling permutations that can be interpreted in terms of ordered trees and forests. We prove that the number of generalized Stirling permutations with a fixed number of ascents is given by a natural…

Combinatorics · Mathematics 2021-05-11 J. Fernando Barbero G. , Jesús Salas , Eduardo J. S. Villaseñor

Carlitz and Scoville introduced the polynomials $A_n(x,y|{\alpha},{\beta})$, which we refer to as the $(\alpha, \beta)$-Eulerian polynomials. These polynomials count permutations based on Eulerian-Stirling statistics, including descents,…

Combinatorics · Mathematics 2023-10-17 Kathy Q. Ji

Motivated by the question of whether Chow polynomials of matroids have only real roots, this article revisits the known relationship between Eulerian polynomials and the Hilbert series of Chow rings of permutohedral varieties. This is done…

Combinatorics · Mathematics 2024-10-21 Basile Coron

Eulerian polynomials record the distribution of descents over permutations. Caylerian polynomials likewise record the distribution of descents over Cayley permutations, where a Cayley permutation is a word of positive integers such that if…

Combinatorics · Mathematics 2025-07-31 Giulio Cerbai , Anders Claesson

We study real sequences $\{a_{n}\}_{n\in \mathbb{N}}$ that eventually agree with a polynomial. We show that if the numerator polynomial of its rational generating series is of degree $s$ and has only nonnegative coefficients, then the…

Combinatorics · Mathematics 2016-05-04 Katharina Jochemko

We introduce rook-Eulerian polynomials, a generalization of the classical Eulerian polynomials arising from complete rook placements on Ferrers boards, and prove that they are real-rooted. We show that a natural context in which to…

Combinatorics · Mathematics 2025-02-11 Per Alexandersson , Aryaman Jal , Maena Quemener

We introduce a family of quasisymmetric functions called {\em Eulerian quasisymmetric functions}, which have the property of specializing to enumerators for the joint distribution of the permutation statistics, major index and excedance…

Combinatorics · Mathematics 2008-05-19 John Shareshian , Michelle L. Wachs

Colored multiset Eulerian polynomials are a common generalization of MacMahon's multiset Eulerian polynomials and the colored Eulerian polynomials, both of which are known to satisfy well-studied distributional properties including…

Combinatorics · Mathematics 2025-07-29 Danai Deligeorgaki , Bin Han , Liam Solus

Let $f$ and $F$ be two polynomials satisfying $F(x)=u(x)f(x)+v(x)f'(x)$. We characterize the relation between the location and multiplicity of the real zeros of $f$ and $F$, which generalizes and unifies many known results, including the…

Combinatorics · Mathematics 2010-08-17 S. -M. Ma , Yi Wang

In this paper, we explore (slightly generalized) $f$-Eulerian polynomials introduced by Stanley and frequently appearing in combinatorics. Notable special cases include the classical Eulerian polynomials, the generating polynomials of order…

Combinatorics · Mathematics 2025-09-18 Dmitrii Karp , Anna Vishnyakova

It is well-known that the Eulerian polynomials, which count permutations in $S_n$ by their number of descents, give the $h$-polynomial/$h$-vector of the simple polytopes known as permutohedra, the convex hull of the $S_n$-orbit for a…

Algebraic Geometry · Mathematics 2010-09-10 Letitia Golubitsky

Using the theory of exponential Riordan arrays and orthogonal polynomials, we demonstrate that the "descending power" Eulerian polynomials, and their once shifted sequence, are moment sequences for simple families of orthogonal polynomials,…

Combinatorics · Mathematics 2011-05-17 Paul Barry

We prove several identities expressing polynomials counting permutations by various descent statistics in terms of Eulerian polynomials, extending results of Stembridge, Petersen, and Br\"and\'en. Additionally, we find $q$-exponential…

Combinatorics · Mathematics 2018-06-13 Yan Zhuang

Univariate polynomial root-finding is a classical subject, still important for modern computing. Frequently one seeks just the real roots of a polynomial with real coefficients. They can be approximated at a low computational cost if the…

Symbolic Computation · Computer Science 2017-04-14 Victor Y. Pan , Liang Zhao

The aim of this paper is twofold. Firstly, we investigate a finite sum involving the generalized falling factorial polynomials, in some special cases of which we express it in terms of the degenerate Stirling numbers of the second kind, the…

Number Theory · Mathematics 2023-01-11 Taekyun Kim , Dae San Kim

Based on the Hermite--Biehler theorem, we simultaneously prove the real-rootedness of Eulerian polynomials of type $D$ and the real-rootedness of affine Eulerian polynomials of type $B$, which were first obtained by Savage and Visontai by…

Combinatorics · Mathematics 2015-04-15 Arthur L. B. Yang , Philip B. Zhang

Gessel conjectured that the two-sided Eulerian polynomial, recording the common distribution of the descent number of a permutation and that of its inverse, has non-negative integer coefficients when expanded in terms of the gamma basis.…

Combinatorics · Mathematics 2018-04-24 Ron M. Adin , Eli Bagno , Estrella Eisenberg , Shulamit Reches , Moriah Sigron

Motivated by the classical Eulerian number, descent and excedance numbers in the hyperoctahedral groups, an triangular array from staircase tableaux and so on, we study a triangular array $[\mathcal {T}_{n,k}]_{n,k\ge 0}$ satisfying the…

Combinatorics · Mathematics 2020-07-27 Bao-Xuan Zhu