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相关论文: A $q$-analog of the Stirling-Eulerian Polynomials

200 篇论文

Weights of permutations were originally introduced by Dugan, Glennon, Gunnells, and Steingr\'imsson (Journal of Combinatorial Theory, Series A 164:24-49, 2019) in their study of the combinatorics of tiered trees. Given a permutation…

组合数学 · 数学 2020-12-03 Aman Agrawal , Caroline Choi , Nathan Sun

In this paper, we characterize a duality relation between Eulerian recurrences and Eulerian recurrence systems, which generalizes and unifies Hermite-Biehler decompositions of several enumerative polynomials, including flag descent…

组合数学 · 数学 2020-10-20 Shi-Mei Ma , Jun Ma , Jean Yeh , Yeong-Nan Yeh

A Smirnov word is a word over the positive integers in which adjacent letters must be different. A symmetric function enumerating these words by descent number arose in the work of Shareshian and the second named author on $q$-Eulerian…

组合数学 · 数学 2019-04-29 Brittney Ellzey , Michelle L. Wachs

In the context of Stirling polynomials, Gessel and Stanley introduced the definition of Stirling permutation, which has attracted extensive attention over the past decades. Recently, we introduced Stirling permutation code and provided…

组合数学 · 数学 2024-06-11 Shi-Mei Ma , Hao Qi , Jean Yeh , Yeong-Nan Yeh

The classical Eulerian polynomials can be expanded in the basis $t^{k-1}(1+t)^{n+1-2k}$ ($1\leq k\leq\lfloor (n+1)/2\rfloor$) with positive integral coefficients. This formula implies both the symmetry and the unimodality of the Eulerian…

组合数学 · 数学 2012-04-02 Guoniu Han , Frédéric Jouhet , Jiang Zeng

This paper is concerned with multivariate refinements of the gamma-positivity of Eulerian polynomials by using the succession and fixed point statistics. Properties of the enumerative polynomials for permutations, signed permutations and…

组合数学 · 数学 2020-08-11 Shi-Mei Ma , Jun Ma , Jean Yeh , Yeong-Nan Yeh

We prove that the enumerative polynomials of quasi-Stirling permutations of multisets with respect to the statistics of plateaux, descents and ascents are partial $\gamma$-positive, thereby confirming a recent conjecture posed by Lin, Ma…

组合数学 · 数学 2021-07-14 Sherry H. F. Yan , Yunwei Huang , Lihong Yang

The $1/k$-Eulerian polynomials $A^{(k)}_{n}(x)$ were introduced as ascent polynomials over $k$-inversion sequences by Savage and Viswanathan. The bi-$\gamma$-positivity of the $1/k$-Eulerian polynomials $A^{(k)}_{n}(x)$ was known but to…

组合数学 · 数学 2025-01-22 Sherry H. F. Yan , Xubo Yang , Zhicong Lin

Motivated by recent work on (re)mixed Eulerian numbers, we provide a combinatorial interpretation of a subfamily of the remixed Eulerian numbers introduced by Nadeau and Tewari. More specifically, we show that these numbers can be realized…

组合数学 · 数学 2025-09-03 Chao Xu , Jiang Zeng

We provide combinatorial interpretation for the $\gamma$-coefficients of the basic Eulerian polynomials that enumerate permutations by the excedance statistic and the major index as well as the corresponding $\gamma$-coefficients for…

组合数学 · 数学 2015-05-01 Zhicong Lin , Jiang Zeng

A formula of Stembridge states that the permutation peak polynomials and descent polynomials are connected via a quadratique transformation. The aim of this paper is to establish the cycle analogue of Stembridge's formula by using cycle…

组合数学 · 数学 2020-07-30 Bin Han , Jianxi Mao , Jiang Zeng

The motivation of this paper is to investigate the joint distribution of succession and Eulerian statistics. We first investigate the enumerators for the joint distribution of descents, big ascents and successions over all permutations in…

组合数学 · 数学 2024-01-09 Shi-Mei Ma , Hao Qi , Jean Yeh , Yeong-Nan Yeh

We present exponential generating function analogues to two classical identities involving the ordinary generating function of the complete homogeneous symmetric functions. After a suitable specialization the new identities reduce to…

组合数学 · 数学 2017-12-01 Rafael S. González D'León

The alternating descent statistic on permutations was introduced by Chebikin as a variant of the descent statistic. We show that the alternating descent polynomials on permutations are unimodal via a five-term recurrence relation. We also…

组合数学 · 数学 2020-11-06 Zhicong Lin , Shi-Mei Ma , David G. L. Wang , Liuquan Wang

Let $A_{n,i,j}$ be the number of permutations on $[n]$ with $(i-1)$ descents and $(j-1)$ inverse descents.Carlitz, Roselle and Scoville in 1966 first revealed some combinatorial and arithmetic properties of $A_{n,i,j}$,which contain a…

组合数学 · 数学 2024-10-07 Frank Z. K. Li , Xunhao Liu

We prove that the enumerative polynomials of generalized Stirling permutations by the statistics of plateaux, descents and ascents are partial $\gamma$-positive. Specialization of our result to the Jacobi-Stirling permutations confirms a…

组合数学 · 数学 2020-05-15 Zhicong Lin , Jun Ma , Philip B. Zhang

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…

组合数学 · 数学 2024-07-17 Giulio Cerbai , Anders Claesson

We find the exponential generating function for permutations with all valleys even and all peaks odd, and use it to determine the asymptotics for its coefficients, answering a question posed by Liviu Nicolaescu. The generating function can…

组合数学 · 数学 2014-08-11 Ira M. Gessel , Yan Zhuang

The aim of this paper is to give a new approach to modified $q$-Bernstein polynomials for functions of several variables. By using these polynomials, the recurrence formulas and some new interesting identities related to the second Stirling…

数论 · 数学 2019-07-04 Serkan Araci , Mehmet Acikgoz , Hassan Jolany , Armen Bagdasaryan

The classical Eulerian polynomials $A_n(t)$ are known to be gamma positive. Define the positive Eulerian polynomial $A_n^+(t)$ as the polynomial obtained when we sum descents over the alternating group. We show that $A_n^+(t)$ is gamma…

组合数学 · 数学 2018-12-06 Hiranya Kishore Dey , Sivaramakrishnan Sivasubramanian