Results 61 to 70 of about 29,782 (219)
Finite models for positive combinatorial and exponential algebra
Bulletin of the London Mathematical Society, EarlyView.Abstract We use high girth, high chromatic number hypergraphs to show that there are finite models of the equational theory of the semiring of non‐negative integers whose equational theory has no finite axiomatisation, and show this also holds if factorial, fixed base exponentiation and operations for binomial coefficients are adjoined.
Tumadhir Alsulami, Marcel Jackson
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On the closure of the extended bicyclic semigroup
Karpatsʹkì Matematičnì Publìkacìï, 2011 In the paper we study the semigroup $mathscr{C}_{mathbb{Z}}$which is a generalization of the bicyclic semigroup. We describemain algebraic properties of the semigroup$mathscr{C}_{mathbb{Z}}$ and prove that every non-trivialcongruence $mathfrak{C}$ on the
I. R. Fihel, O. V. Gutik
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Semigroup C⁎-algebras and amenability of semigroups
Journal of Functional Analysis, 2012 39 pages; corrected and revised version, new construction added in section ...
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Growth problems in diagram categories
Bulletin of the London Mathematical Society, EarlyView.Abstract In the semisimple case, we derive (asymptotic) formulas for the growth rate of the number of summands in tensor powers of the generating object in diagram/interpolation categories.
Jonathan Gruber, Daniel Tubbenhauer
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ON HYBRID INTERIOR IDEALS IN SEMIGROUPS
Проблемы анализа, 2019 In this paper, we introduce the notion of hybrid interior ideals and hybrid characteristic interior ideals of a semigroup. We obtain some equivalent conditions for a hybrid structure to be a hybrid interior ideal of a semigroup.
K. Porselvi, B. Elavarasan
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Is every product system concrete?
Transactions of the London Mathematical Society, Volume 12, Issue 1, December 2025.Abstract Is every product system of Hilbert spaces over a semigroup P$P$ concrete, that is, isomorphic to the product system of an E0$E_0$‐semigroup over P$P$? The answer is no if P$P$ is discrete, cancellative and does not embed in a group. However, we show that the answer is yes for a reasonable class of semigroups.
S. Sundar
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Commuting Pairs in Quasigroups
Journal of Combinatorial Designs, Volume 33, Issue 11, Page 418-427, November 2025.ABSTRACT A quasigroup is a pair ( Q , ∗ ), where Q is a nonempty set and ∗ is a binary operation on Q such that for every ( a , b ) ∈ Q 2, there exists a unique ( x , y ) ∈ Q 2 such that a ∗ x = b = y ∗ a. Let ( Q , ∗ ) be a quasigroup. A pair ( x , y ) ∈ Q 2 is a commuting pair of ( Q , ∗ ) if x ∗ y = y ∗ x.
Jack Allsop, Ian M. Wanless
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On (m, n)-ideals and (m, n)-regular ordered semigroups [PDF]
Songklanakarin Journal of Science and Technology (SJST), 2016 Let m, n be non-negative integers. A subsemigroup A of an ordered semigroup (S, , is called an (m, n)-ideal of S if (i) Am SAn A, and (ii) if x A, y S such that y x, then y A. In this paper, necessary and sufficient conditions for every (
Limpapat Bussaban, Thawhat Changphas
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Locally adequate semigroup algebras
Open Mathematics, 2016 We build up a multiplicative basis for a locally adequate concordant semigroup algebra by constructing Rukolaĭne idempotents. This allows us to decompose the locally adequate concordant semigroup algebra into a direct product of primitive abundant 0-J*$0{
Ji Yingdan, Luo Yanfeng
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Mathematical Methods in the Applied Sciences, Volume 48, Issue 16, Page 14890-14908, 15 November 2025.ABSTRACT We analyze nonlinear degenerate coupled partial differential equation (PDE)‐PDE and PDE‐ordinary differential equation (ODE) systems that arise, for example, in the modelling of biofilm growth. One of the equations, describing the evolution of a biomass density, exhibits degenerate and singular diffusion.
K. Mitra, S. Sonner
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