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111.
张人智 《南昌大学学报(理科版)》1992,16(1):1
假设S是有0,1的半群,τ是S-系的遗传扭论,对任意的右S-系M,Tτ(M)是M的τ-扭根。x∈Tτ(M)当且仅当存在某个τ-稠密右同余ρ,使得对任意的(S1,S2)∈ρ均有xs1=xs2,同时,当右S-系M是τ-扭自由时,M的τ-稠密同余是M的本质同余,特别,对忠实的遗传扭论τ,S的τ-稠密右同余是S 相似文献
112.
漆芝南 《南昌大学学报(理科版)》1991,15(4):1
本文研究分配格的理想,并考虑了分配格的一些类,对它们的性质及彼此之间的关系进行了探讨,得到了初步结果,这些结果对分配格的更深入研究是有益的。 相似文献
113.
The discrete logarithm problem in various finite abelian groups is the basis for some well known public key cryptosystems. Recently, real quadratic congruence function fields were used to construct a public key distribution system. The security of this public key system is based on the difficulty of a discrete logarithm problem in these fields. In this paper, we present a probabilistic algorithm with subexponential running time that computes such discrete logarithms in real quadratic congruence function fields of sufficiently large genus. This algorithm is a generalization of similar algorithms for real quadratic number fields.
114.
Thomas G. McLaughlin 《Mathematical Logic Quarterly》2002,48(3):323-342
In his long and illuminating paper [1] Joe Barback defined and showed to be non‐vacuous a class of infinite regressive isols he has termed “complete y torre” (CT) isols. These particular isols a enjoy a property that Barback has since labelled combinatoriality. In [2], he provides a list of properties characterizing the combinatoria isols. In Section 2 of our paper, we extend this list of characterizations to include the fact that an infinite regressive isol X is combinatorial if and only if its associated Dekker semiring D (X) satisfies all those Π2 sentences of the anguage LN for isol theory that are true in the set ω of natural numbers. (Moreover, with X combinatorial, the interpretations in D(X)of the various function and relation symbols of LN via the “lifting ” to D(X) of their Σ1 definitions in ω coincide with their interpretations via isolic extension.) We also note in Section 2 that Π2(L)‐correctness, for semirings D(X), cannot be improved to Π 3(L)‐correctness, no matter how many additional properties we succeed in attaching to a combinatoria isol; there is a fixed (L) sentence that blocks such extension. (Here L is the usual basic first‐order language for arithmetic.) In Section 3, we provide a proof of the existence of combinatorial isols that does not involve verification of the extremely strong properties that characterize Barback's CT isols. 相似文献
115.
MS-代数的理想和同余关系 总被引:3,自引:1,他引:2
王尊全 《纯粹数学与应用数学》2004,20(4):389-392
给出了MS-代数L的理想I=(d]可以成为某个同余关系核的充要条件;分别给出了以L的理想I=(d]为核的最小同余关系及最大同余关系的充要条件. 相似文献
116.
环中关于理想同余的粗糙集的性质 总被引:1,自引:0,他引:1
讨论了环中由理想同余关系所决定的下、上近似的一些特殊性质. 相似文献
117.
Larry Ericksen 《Mathematica Slovaca》2009,59(3):261-274
The divisibility of numbers is obtained by iteration of the weighted sum of their integer digits. Then evaluation of the related
congruences yields information about the primality of numbers in certain recursive sequences. From the row elements in generalized
Delannoy triangles, we can verify the primality of any constellation of numbers. When a number set is not a prime constellation,
we can identify factors of their composite numbers. The constellation primality test is proven in all generality, and examples
are given for twin primes, prime triplets, and Sophie Germain primes.
相似文献
118.
Neutral elements and central elements are characterized in different classes of posets such as sectionally semi-complemented
posets, atomistic posets etc.
相似文献
119.
Marcel Erné 《Mathematical Logic Quarterly》2009,55(6):572-586
We compare diverse degrees of compactness and finiteness in Boolean algebras with each other and investigate the influence of weak choice principles. Our arguments rely on a discussion of infinitary distributive laws and generalized prime elements in Boolean algebras. In ZF set theory without choice, a Boolean algebra is Dedekind finite if and only if it satisfies the ascending chain condition. The Denumerable Subset Axiom (DS) implies finiteness of Boolean algebras with compact top, whereas the converse fails in ZF. Moreover, we derive from DS the atomicity of continuous Boolean algebras. Some of the results extend to more general structures like pseudocomplemented semilattices (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
120.
设R是含有恒等元1的半环,C是R上的中心子半环.Tn(R)是R上的n阶上三角矩阵C-代数.证明了当R是一个幂等元都是中心元的半环时,映射Φ:Tn(R)→Tn(R)是乘法半群自同构当且仅当存在Tn(R)中的可逆矩阵G和R中的半环自同构τ使得A=(aij)n×n∈Tn(R),均有Φ(A)=G-1τ(A)G.这里τ(A)=(τ(aij))n×n,n2. 相似文献