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Related papers: A note on the span of Hadamard products of vectors

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Let $S(x)$ be the number of $n \leq x$ for which a Hadamard matrix of order $n$ exists. Hadamard's conjecture states that $S(x)$ is about $x/4$. From Paley's constructions of Hadamard matrices, we have that \[ S(x) = \Omega(x/\log x). \] In…

Combinatorics · Mathematics 2010-04-28 Warwick de Launey , Daniel M. Gordon

The Hadamard Extension of a matrix is the matrix consisting of all Hadamard products of subsets of its rows. This construction arises in the context of identifying a mixture of product distributions on binary random variables: full column…

Machine Learning · Computer Science 2021-02-16 Spencer L. Gordon , Leonard J. Schulman

In his study of Nekrasov-Okounkov type formulas on "partition theoretic" expressions for families of infinite products, Han discovered seemingly unrelated $q$-series that are supported on precisely the same terms as these infinite products.…

Number Theory · Mathematics 2014-12-16 Amanda Clemm

We prove several results about functions which preserve the Schur-Agler class under Hadamard or coefficient-wise product. First, functions which preserve the Schur class necessarily preserve the Schur-Agler class. Second, ``moments'' of…

Functional Analysis · Mathematics 2025-07-15 Greg Knese

We consider inhomogeneous matrix products over max-plus algebra, where the matrices in the product satisfy certain assumptions under which the matrix products of sufficient length be rank-one, as it was shown in [6][L. Shue, B.D.O.…

Rings and Algebras · Mathematics 2019-04-15 Arthur Kennedy Cochran Patrick , Sergei Sergeev , Štefan Berežný

We give a simple proof of a crucial lemma that is established in [1, Lemma 2.1] by induction, and plays important roles in that paper and [2].

Functional Analysis · Mathematics 2018-07-12 Shibo Liu

We generalize the tensor product theory for modules for a vertex operator algebra previously developed in a series of papers by the first two authors to suitable module categories for a ``conformal vertex algebra'' or even more generally,…

Quantum Algebra · Mathematics 2007-05-23 Yi-Zhi Huang , James Lepowsky , Lin Zhang

In this article, we explain the link between Pohlen's extended Hadamard product and the holomorphic cohomological convolution on $\mathbb{C}^*$. For this purpose, we introduce a generalized Hadamard product, which is defined even if the…

Complex Variables · Mathematics 2018-12-18 Christophe Dubussy , Jean-Pierre Schneiders

This is the sixth part in a series of papers in which we introduce and develop a natural, general tensor category theory for suitable module categories for a vertex (operator) algebra. In this paper (Part VI), we construct the appropriate…

Quantum Algebra · Mathematics 2012-05-14 Yi-Zhi Huang , James Lepowsky , Lin Zhang

We study examples of fourth-order Picard-Fuchs operators that are Hadamard products of two second-order Picard-Fuchs operators. Each second-order Picard-Fuchs operator is associated with a family of elliptic curves, and the Hadamard product…

High Energy Physics - Theory · Physics 2023-12-25 Mohamed Elmi

We study the Hadamard product of the linear forms defining a hyperplane arrangement with those of its dual, which we view as generating an ideal in a certain polynomial ring. We use this ideal, which we call the ideal of pairs, to study…

Combinatorics · Mathematics 2022-02-08 Avi Steiner , Graham Denham

In one of his papers, the author introduces the class of Farkas-related vectors for which a version of Farkas' lemma over integers is derived. In this paper, two similar classes are introduced and studied.

Combinatorics · Mathematics 2015-08-31 Masood Aryapoor

We are interested to bound from below the number of distinct dot products determined by a finite set of points $P$ in the Euclidean plane. In this paper, we build on the work of B. Hanson, O. Roche-Newton, and S. Senger, to obtain the…

Combinatorics · Mathematics 2025-02-19 Michalis Kokkinos

This is a remark on a recent post by P. Denton, S. Parke, T. Tao, X. Zhang, Eigenvectors from eigenvalues, arXiv:1908.03795v1

Rings and Algebras · Mathematics 2019-11-21 Carlos Tomei

An argument of Y. Nikonorov completes the proof of Theorem 2.5 in "Bounded Isometries and Homogeneous Quotients", JGA 27 (2017), 56--64 [arXiv:1502.04276].

Algebraic Geometry · Mathematics 2021-11-11 Joseph A. Wolf

We first summarize joint work on several preliminary canonical Lambert series factorization theorems. Within this article we establish new analogs to these original factorization theorems which characterize two specific primary cases of the…

Number Theory · Mathematics 2017-12-05 Maxie D. Schmidt

We give a new proof for a product formula of Jacobi which turns out to be equivalent to a $q$-trigonometric product which was stated without proof by Gosper. We apply this formula to derive a $q$-analogue for the Gauss multiplication…

Number Theory · Mathematics 2019-01-29 Mohamed El Bachraoui , József Sándor

As a direct application of Dilworth truncations of polymatroids, we give short proofs of two theorems: Bernstein's characterisation of algebraic matroids coming from the Hadamard product of two linear spaces, and a formula for the dimension…

Combinatorics · Mathematics 2025-08-08 Dario Antolini , Sean Dewar , Shin-ichi Tanigawa

In the paper are proved theorems, which amplify the results of my paper "On the difference equation of Poincare type (Part 3)", Max-Plank-Institut fuer Mathematik, Bonn, Preprint Series, 2004, 09, 1-34.

Number Theory · Mathematics 2007-05-23 L. A. Gutnik

We find a necessary and sufficient condition for the existence of the tensor product of modules over a Lie conformal algebra. We provide two algebraic constructions of the tensor product. We show the relation between tensor product and…

Quantum Algebra · Mathematics 2022-12-19 Jose I. Liberati