Results 11 to 20 of about 226 (46)
A generalization of Alternating Sign Matrices [PDF]
, 2013 In alternating sign matrices the first and last nonzero entry in each row and column is specified to be +1. Such matrices always exist. We investigate a generalization by specifying independently the sign of the first and last nonzero entry in each row
Brualdi, Richard A., Kim, Hwa Kyung
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Studying the inertias of LCM matrices and revisiting the Bourque-Ligh conjecture [PDF]
, 2019 Let $S=\{x_1,x_2,\ldots,x_n\}$ be a finite set of distinct positive integers. Throughout this article we assume that the set $S$ is GCD closed. The LCM matrix $[S]$ of the set $S$ is defined to be the $n\times n$ matrix with $\mathrm{lcm}(x_i,x_j)$ as ...
Haukkanen, Pentti +2 more
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On Generalized Jacobsthal and Jacobsthal-Lucas polynomials
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2016 In this paper we introduce a generalized Jacobsthal and Jacobsthal-Lucas polynomials, Jh,n and jh,n, respectively, that consist on an extension of Jacobsthal's polynomials Jn(𝑥) and Jacobsthal-Lucas polynomials jn(𝑥).
Catarino Paula, Morgado Maria Luisa
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Fibonacci and Telephone Numbers in Extremal Trees
Discussiones Mathematicae Graph Theory, 2018 In this paper we shall show applications of the Fibonacci numbers in edge-coloured trees. In particular we determine the successive extremal graphs in the class of trees with respect to the number of (A, 2B)-edge colourings.
Bednarz Urszula, Włoch Iwona
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Jacobsons Lemma fails for nil-clean 2 × 2 integral matrices
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2020 We show that for two 2 × 2 integral matrices A, B, if the product AB is nil-clean then BA may not be nil-clean. Despite the fact that for many special cases, BA is also nil-clean, we finally found three counterexamples.
Călugăreanu Grigore, Pop Horia F.
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Rank relations between a {0, 1}-matrix and its complement
Open Mathematics, 2018 Let A be a {0, 1}-matrix and r(A) denotes its rank. The complement matrix of A is defined and denoted by Ac = J − A, where J is the matrix with each entry being 1.
Ma Chao, Zhong Jin
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Generalized Pell Equations for 2 × 2 Matrices
Discussiones Mathematicae - General Algebra and Applications, 2017 In this paper we consider the solutions of the generalized matrix Pell equations X2 − dY2 = cI, where X and Y are 2 × 2 matrices over ℤ, d is a non-zero (positive or negative) square-free integer, c is an arbitrary integer and I is the 2 × 2 identity ...
Cohen Boaz
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Inverses and eigenvalues of diamondalternating sign matrices
Special Matrices, 2014 An n × n diamond alternating sign matrix (ASM) is a (0, +1, −1)-matrix with ±1 entries alternatingand arranged in a diamond-shaped pattern. The explicit inverse (for n even) or generalized inverse (for nodd) of a diamond ASM is derived.
Catral Minerva +3 more
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Small-span Hermitian matrices over quadratic integer rings
, 2013 Building on the classification of all characteristic polynomials of integer symmetric matrices having small span (span less than 4), we obtain a classification of small-span polynomials that are the characteristic polynomial of a Hermitian matrix over ...
Greaves, Gary
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Eulerian polynomials as moments, via exponential Riordan arrays [PDF]
, 2011 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, which we ...
Barry, Paul
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