Results 41 to 50 of about 487 (185)
On the automorphisms of the power semigroups of a numerical semigroup
Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.Abstract If H$H$ is a numerical semigroup (i.e., a cofinite subset of the non‐negative integers closed under addition), then the collection of all non‐empty subsets of H$H$ forms a semigroup P(H)$\mathcal {P}(H)$ under the sumset operation induced by addition in H$H$.
Salvatore Tringali, Kerou Wen
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On the tightness of left‐invariant contact structures
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract We prove that all left‐invariant contact structures on three‐dimensional Lie groups are tight. The argument is based on Riemannian methods and establishes a unique factorization property for any Lie group admitting a left‐invariant contact structure, other than SU(2)$\mathrm{SU}(2)$. We then make use of such factorization property to construct
Eugenio Bellini
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Some Classification Theorems and Endomorphisms in New Classes
Mathematics, 2023 Let ℧ be a prime ring of char(℧) ≠2 with its center Z. This article introduces new classes of endomorphisms and investigates how they relate to antiautomorphisms of prime rings and the commutativity of prime rings.
Hafedh Alnoghashi +4 more
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The singularity category and duality for complete intersection groups
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract If G$G$ is a finite group, the structure of the modular representation theory depends on the cochains C∗(BG;k)$C^*(BG; k)$, viewed as a commutative ring spectrum. We consider here its singularity category (in the sense of the author and Stevenson [Adv. Math.
J. P. C. Greenlees
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On the cohomology of finite‐dimensional nilpotent groups and lie rings
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract We establish vanishing results for the first cohomology group of nilpotent groups and Lie rings when the submodule of invariants is trivial. Our results are obtained within a model‐theoretic setting, namely for structures that are definable in a finite‐dimensional theory, which encompasses algebraic groups over algebraically closed fields ...
Samuel Zamour
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A characterization of singular endomorphisms of a barrelled Pták space
International Journal of Mathematics and Mathematical Sciences, 1982 The concept of topological divisor of zero has been extended to endomorphisms of a locally convex topological vector space (LCTVS). A characterization of singular endomorphisms, similar to that of Yood [1], is obtained for endomorphisms of a barrelled ...
Damir Franekić
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Endomorphisms of the Toeplitz algebra
Учёные записки Казанского университета: Серия Физико-математические науки, 2023 This article describes all injective endomorphisms of the classical Toeplitz algebra. Their connection with endomorphisms of the algebra of continuous functions on the unit circle and with coverings over the unit circle was considered.
S. A. Grigoryan, A. Yu. Kuznetsova
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The N‐prime graph and the Subgroup Isomorphism Problem
Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.Abstract We introduce a directed graph related to a group G$G$, which we call the N‐prime graph ΓN(G)$\Gamma _{\rm {N}}(G)$ of G$G$ and is a refinement of the classical Gruenberg–Kegel graph. The vertices of ΓN(G)$\Gamma _{\rm {N}}(G)$ are the primes p$p$ such that G$G$ has an element of order p$p$, and, for distinct vertices p$p$ and q$q$, the arc q→p$
Emanuele Pacifici +2 more
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Connections with parallel skew-symmetric torsion on sub-Riemannian manifolds
Дифференциальная геометрия многообразий фигур, 2020 On a sub-Riemannian manifold M of contact type, is considered an N-connection defined by the pair (, N), where is an interior metric connection, is an endomorphism of the distribution D.
S. Galaev
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New Pexiderizations of Drygas’ Functional Equation on Abelian Semigroups
Annales Mathematicae Silesianae, 2023 Let (S, +) be an abelian semigroup, let (H, +) be an abelian group which is uniquely 2-divisible, and let ϕ be an endomorphism of S. We find the solutions f, h : S → H of each of the functional equations f(x+y)+f(x+ϕ(y))=h(x)+f(y)+f∘ϕ(y), x,y∈S,f(x+y)+f ...
Aissi Youssef, Zeglami Driss
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