Results 11 to 20 of about 210 (29)
The integer cp-rank of 2 × 2 matrices
Special Matrices, 2019 We show the cp-rank of an integer doubly nonnegative 2 × 2 matrix does not exceed 11.
Laffey Thomas, Šmigoc Helena
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Inertia, positive definiteness and $\ell_p$ norm of GCD and LCM matrices and their unitary analogs [PDF]
, 2017 Let $S=\{x_1,x_2,\dots,x_n\}$ be a set of distinct positive integers, and let $f$ be an arithmetical function. The GCD matrix $(S)_f$ on $S$ associated with $f$ is defined as the $n\times n$ matrix having $f$ evaluated at the greatest common divisor of ...
Haukkanen, Pentti, Tóth, László
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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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Rationality of the zeta function of the subgroups of abelian $p$-groups
, 2017 Given a finite abelian $p$-group $F$, we prove an efficient recursive formula for $\sigma_a(F)=\sum_{\substack{H\leq F}}|H|^a$ where $H$ ranges over the subgroups of $F$.
Ramaré, Olivier
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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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