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In this paper we study unimodality problems for the independence polynomial of a graph, including unimodality, log-concavity and reality of zeros. We establish recurrence relations and give factorizations of independence polynomials for…

Combinatorics · Mathematics 2010-08-17 Yi Wang , Bao-Xuan Zhu

Given a graph $G$, its independence sequence is the integral sequence $a_1,a_2,...,a_n$, where $a_i$ is the number of independent sets of vertices of size i. In the late 80's Alavi, Erdos, Malde, Schwenk showed that this sequence need not…

Combinatorics · Mathematics 2025-10-28 Eric Ramos , Sunny Sun

This paper is devoted to the study of the log-convexity of combinatorial sequences. We show that the log-convexity is preserved under componentwise sum, under binomial convolution, and by the linear transformations given by the matrices of…

Combinatorics · Mathematics 2010-08-17 Li Liu , Yi Wang

We study rational homology groups of one-point compactifications of spaces of complex monic polynomials with multiple roots. These spaces are indexed by number partitions. A standard reformulation in terms of quotients of orbit arrangements…

Combinatorics · Mathematics 2007-05-23 Dmitry N. Kozlov

In this paper, we investigate two properties concerning the unimodality of the $\delta$-vectors of lattice polytopes, which are log-concavity and alternatingly increasingness. For lattice polytopes $\mathcal{P}$ of dimension $d$, we prove…

Combinatorics · Mathematics 2015-04-17 Akihiro Higashitani

The unimodality conjecture posed by Tolman in the conference `Moment maps in Various Geometry" in 2005 states that if (M,w) is a 2n-dimensional smooth compact symplectic manifold equipped with a Hamiltonian circle action with only isolated…

Symplectic Geometry · Mathematics 2015-03-10 Yunhyung Cho

Simion had a unimodality conjecture concerning the number of lattice paths in a rectangular grid with the Ferrers diagram of a partition removed. Hildebrand recently showed the stronger result that these numbers are log concave. Here we…

Combinatorics · Mathematics 2008-09-10 Yi Wang

The homological information about a filtered simplicial complex over the poset of positive real numbers is often presented by a barcode which depicts the evolution of the associated Betti numbers. However, there is a wonderfully complex…

Algebraic Topology · Mathematics 2022-09-05 İsmail Güzel , Atabey Kaygun

Univariate polynomial root-finding is both classical and 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 polynomial…

Numerical Analysis · Mathematics 2014-07-01 Victor Y. Pan

New criteria are shown that certain combinations of finite unimodal polynomials are unimodal. %Given unimodal polynomials with explicit expressions and dependent recursion relations, we propose an approach to determine their modes. As…

Combinatorics · Mathematics 2014-01-23 Liangxia Wan

We give a short proof of the log-concavity of the coefficients of the reduced characteristic polynomial of a matroid. The proof uses an extension of the theory of Lorentzian polynomials to convex cones, and reproves the Hodge-Riemann…

Combinatorics · Mathematics 2021-10-12 Petter Brändén , Jonathan Leake

Unimodality, pivotal in statistical analysis, offers insights into dataset structures and drives sophisticated analytical procedures. While unimodality's confirmation is straightforward for one-dimensional data using methods like…

Methodology · Statistics 2024-07-08 Prodromos Kolyvakis , Aristidis Likas

Gao and Xie (2021) conjectured that the inverse Kazhdan-Lusztig polynomial of any matroid is log-concave. Although the inverse Kazhdan-Lusztig polynomial may not always have only real roots, we conjecture that the Hadamard product of an…

Combinatorics · Mathematics 2025-04-25 Matthew H. Y. Xie , Philip B. Zhang

We study the stratification of the space of monic polynomials with real coefficients according to the number and multiplicities of real zeros. In the first part, for each of these strata we provide a purely combinatorial chain complex…

Combinatorics · Mathematics 2016-09-06 Volkmar Welker , Boris Shapiro

In 1987, Alavi, Malde, Schwenk and Erd\H{o}s conjectured that the independence polynomials of trees are unimodal. Subsequently, many researchers proposed strengthening this conjecture to log-concavity. In 2023, Kadrawi, Levit, Yosef, and…

Combinatorics · Mathematics 2026-03-04 Grace M. X. Li

This paper investigates the independence polynomials arising from iterated strong products of cycle graphs, examining their algebraic symmetries and combinatorial structures. Leveraging modular arithmetic and Galois theory, we establish…

Combinatorics · Mathematics 2026-01-13 Todd Hildebrant

For any matroid $M$, we compute the Tutte polynomial $T_M(x,y)$ using the mixed intersection numbers of certain classes in the combinatorial Chow ring $A^\bullet(M)$ arising from hypersimplices. Using the mixed Hodge-Riemann relations, we…

Algebraic Geometry · Mathematics 2023-03-27 Andrew Berget , Hunter Spink , Dennis Tseng

With the exponential surge in diverse multi-modal data, traditional uni-modal retrieval methods struggle to meet the needs of users seeking access to data across various modalities. To address this, cross-modal retrieval has emerged,…

Information Retrieval · Computer Science 2024-10-01 Tianshi Wang , Fengling Li , Lei Zhu , Jingjing Li , Zheng Zhang , Heng Tao Shen

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

Many combinatorial proofs rely on induction. When these proofs are formulated in traditional language, they can be bulky and unmanageable. Coalgebras provide a language which can reduce reduce many inductive proofs in graded poset theory to…

Combinatorics · Mathematics 2022-10-07 MLE Slone