Results 21 to 30 of about 226 (46)
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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Special MatricesA nonzero element aa is called 1-Sylvester in a ring RR, if there exist b,c∈Rb,c\in R such that 1=ab+ca1=ab+ca. In this article, we study such elements, mainly in matrix rings over commutative rings.
Călugăreanu Grigore
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Commutators and Anti-Commutators of Idempotents in Rings
, 2018 We show that a ring $\,R\,$ has two idempotents $\,e,e'\,$ with an invertible commutator $\,ee'-e'e\,$ if and only if $\,R \cong {\mathbb M}_2(S)\,$ for a ring $\,S\,$ in which $\,1\,$ is a sum of two units. In this case, the "anti-commutator" $\,ee'+e'e\
Khurana, Dinesh, Lam, T. Y.
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On (k1A1, k2A2, k3A3)-Edge Colourings in Graphs and Generalized Jacobsthal Numbers
Annales Mathematicae SilesianaeIn this paper we introduce a new kind of generalized Jacobsthal numbers in a distance sense. We give the identities and matrix representations for them and their connections with the Fibonacci and the Pell numbers. We also describe the interpretations of
Piejko Krzysztof, Trojnar-Spelina Lucyna
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The number of rational points of some classes of algebraic varieties over finite fields
Open MathematicsLet Fq{{\mathbb{F}}}_{q} be the finite field of characteristic pp and Fq*=Fq\{0}{{\mathbb{F}}}_{q}^{* }\left={{\mathbb{F}}}_{q}\backslash \left\{0\right\}.
Zhu Guangyan +3 more
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Special MatricesDeterminants of structured matrices play a fundamental role in both pure and applied mathematics, with wide-ranging applications in linear algebra, combinatorics, coding theory, and numerical analysis.
Martinez-Moro Edgar +2 more
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The Maximum Order of Reduced Square(0, 1)-Matrices with a Given Rank [PDF]
We look for the maximum order of a square (0, 1)-matrix A with a fixed rank r, provided A has no repeated rows or columns. If A is the adjacency matrix of a graph, Kotlov and Lovász [J. Graph Theory 23, 1996] proved that the maximum order equals Θ(2r/2).
Haemers, W.H., Peeters, M.J.P.
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Development and Preproduction of 15B36Cr Steel for Track Link
Teshugang, 2019 The Φ60 mm 15B36Cr steel two furnace for Track Link (/% : 0.30 ~0.37C、0.15 〜0.30Si、1.20 ~ 1.50Mn、≤ 0. 040P、 ≤ 0.050S、0.20 ~ 0.40Cr、≤ 0. 25Ni、≤ 0.35Cu、≤ 0.06Mo、0.0005 - 0.0030B) was produced by 90 t LD with top-bottom blowing-LF-RH- 200 mm x200 mm billet ...
梁佰战, 郑力宁, 肖波
doaj
Monotonicity of the number of positive entries in nonnegative matrix powers. [PDF]
J Inequal Appl, 2018 Xie Q.
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A library of lineage-specific driver lines connects developing neuronal circuits to behavior in the <i>Drosophila</i> ventral nerve cord. [PDF]
ElifeSoffers JHM +11 more
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