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OI_n的理想K(n,r)的极大逆子半群 总被引:3,自引:0,他引:3
Xn为n元有限集,OIn为Xn上的一切保序严格部分一一变换半群.记K(n,r)={α∈OIn∶|Tmα|≤r}(0≤r≤n-1)则K(n,r)(0≤r≤n-1)是OIn的理想.我们刻划了K(n,r)(1≤r≤n-1)的极大逆子半群. 相似文献
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Zak Mesyan James D. Mitchell Michał Morayne Yann H. Péresse 《Mathematical Logic Quarterly》2012,58(6):424-433
Let $\mathbb {N}^\mathbb {N}Let $\mathbb {N}^\mathbb {N}$ be the semigroup of all mappings on the natural numbers $\mathbb {N}$, and let U and V be subsets of $\mathbb {N}^\mathbb {N}$. We write U?V if there exists a countable subset C of $\mathbb {N}^\mathbb {N}$ such that U is contained in the subsemigroup generated by V and C. We give several results about the structure of the preorder ?. In particular, we show that a certain statement about this preorder is equivalent to the Continuum Hypothesis. The preorder ? is analogous to one introduced by Bergman and Shelah on subgroups of the symmetric group on $\mathbb {N}$. The results in this paper suggest that the preorder on subsemigroups of $\mathbb {N}^\mathbb {N}$ is much more complicated than that on subgroups of the symmetric group. 相似文献
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本文引入弱交换po-半群的概论2,研究这类半群到Archimedean子半群的半格分解,得到了这半群类似于具平凡序的弱交换半群的一个特征,由此在更一般的情形下回答了Kehayopulu在「1」中提出的一个问题,并作为推论得到弱交换poe-半群和具平凡序的弱交换半群的已知结果。 相似文献
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给出了半群中直觉模糊拟理想的等价定义,研究了半群中直觉模糊拟理想的若干性质和刻画,并用直觉模糊拟理想刻画群,完全正则半群和群半格. 相似文献
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Ilinka Dimitrova 《代数通讯》2013,41(5):1821-1826
A partial transformation α on an n-element chain X n is called order-preserving if x ≤ y implies xα ≤yα for all x, y in the domain of α and it is called extensive if x ≤ xα for all x in the domain of α. The set of all partial order-preserving extensive transformations on X n forms a semiband POE n . We determine the maximal subsemigroups as well as the maximal subsemibands of POE n . 相似文献
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The notion of “near isomorphism” for torsion-free Abelian groups of finite rank is well known. In particular, this concept turned out to be of importance for classifying almost completely decomposable groups. We extend near isomorphism to classes of torsion-free Abelian groups of infinite rank which are unions of bcd–groups, this is to say unions of groups which are bounded essential extensions of completely decomposable groups. Moreover, we show that nearly isomorphic groups of this class also have nearly isomorphic endomorphism rings considered as Abelian groups. 相似文献
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Let A, B be associative rings with identity, and (S, ≤) a strictly totally ordered commutative monoid which is also artinian. For any bimodule AMB , we construct a bimodule A[[S]]M[S]B[[S]] and prove that AMB defines a quasi-duality if and only if the bimodule A[[S]]M[S]B[[S]] defines a quasi-duality. As a corollary, it is shown that if a ring A has a quasi-duality then the ring A[[S]] of generalized power series over A has a quasi-duality. 相似文献
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奇异保序变换半群的极大正则子半群 总被引:1,自引:1,他引:0
设On为通常的有限链Xn={1,2,…,n}上的奇异保序变换半群.文中利用格林关系的方法讨论On的极大正则子半群,确定了On的所有的极大正则子半群. 相似文献
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HaoBoYANG XiuLiangYANG 《数学学报(英文版)》2004,20(3):475-482
Let Tn be the full transformation semigroup on the n-element set Xn. For an arbitrary integer r such that 2 ≤ r ≤ n-1, we completely describe the maximal subsemigroups of the semigroup K(n, r) = {α∈Tn : |im α| ≤ r}. We also formulate the cardinal number of such subsemigroups which is an answer to Problem 46 of Tetrad in 1969, concerning the number of subsemigroups of Tn. 相似文献