共查询到20条相似文献,搜索用时 15 毫秒
1.
《Quaestiones Mathematicae》2013,36(3):355-360
Abstract It is shown that Aut ?, the group of homeomorphisms of the rational numbers with the usual topology, has 2 No orbits on the power set P(?). We call S ? ? a moiety if S and its complement in ? are infinite. It is shown that the orbit of any moiety S under Aut ? has cardinality 2No while the orbit of S under Aut(?, ≤), the group of order preserving automorphisms of ?, has cardinality No if and only if S is a finite union of disjoint rational intervals with rational endpoints. 相似文献
2.
本文研究了对称群Sn的所有幂零子群的计算方法.利用添加生成元的方法,获得了S7的全部5119个幂零子群.结果表明此方法是有效的. 相似文献
3.
《Quaestiones Mathematicae》2013,36(2):257-298
Abstract The smallest Fischer sporadic simple group F22 has 14 maximal subgroups up to conjugacy as listed in [2] and [15]. The group 26: SP 6(2) is a maximal subgroup of F 22 of index 694980. We use the technique of the Fischer-Clifford matrices to constuct the character table of the group 26: SP 6(2). The Fischer-Clifford matrices of 26: SP 6(2) are used, together with the character tables of SP 6(2) and a maximal subgroup 25:S 6 SP 6 (2) of index 63, to construct the character table of 26: SP 6 (2). 相似文献
4.
Akito Tsuboi 《Mathematical Logic Quarterly》1992,38(1):101-106
In this note we treat maximal and minimal normal subgroups of a superstable group and prove that these groups are definable under certain conditions. Main tool is a superstable version of Zil'ber's indecomposability theorem. MSC: 03C60. 相似文献
5.
本文采用理论分析与编程判断相结合的方法,获得了Sn的全部极大子群的生成元及子群的阶等结果. 并将结果用于Sn(n=2,3,4,5,6)进行验证,表明了程序判断的正确性,对计算结果进行归纳获得了Sn的递归定义及Sn可由二元生成等结果,可为进一步研究抽象群提供方便. 相似文献
6.
《Quaestiones Mathematicae》2013,36(2):183-190
AbstractThe m'th chromatic number Xm(G) of a graph G is the least number of colours required to colour the vertices of G such that no m-clique of G is mono-coloured. For each k ≥ 2 and m ≥ 2 we determine for which r a graph G with m'th chromatic number k and clique number r exists. We also determine for which n a graph G exists with Xn (G + K) = Xm (G) = k. 相似文献
7.
Hou zixin 《数学年刊B辑(英文版)》1992,13(4):440-454
The author defines the large type Borel subgroups of a reductive algebraic goup,which are used to discuss Langlands' L-goups and the Langlands classification of the admissible representations of reductive algebraic groups over R(see[1,2,5]) and determine all of the Borel subgroups of large type for the classical semisimple Lie groups. 相似文献
8.
群体决策随机偏爱数映射的若干性质 总被引:1,自引:0,他引:1
杨万铨 《高等学校计算数学学报》2008,30(1):8-13
1引言近年来,群体决策在社会选择、福利、经济和军事等领域得到广泛应用,从而其理论研究越来越被人们所重视.20世纪中叶,K.J,Arrow提出了偏爱公理系和不可能性定理,并 相似文献
9.
ON THE STRONG LAW OF LARGE NUMBERS 总被引:1,自引:0,他引:1
This paper introduces the concept of BC sequences and investigates some conditions which imply the strong law of large numbers for these sequences. The authors also study the strong law of large numbers for general random variable sequences. As applications of the result the authors characterize p-smoothableness of Banach space. Some generalizations of Petrov theorem, the Marcinkiewicz-Zygmund theorem and Hoffmann-Jorgensen and Pisier theorem are obtained. 相似文献
10.
1IntroductionsandStatementsInt-,iloIf)4-0'sCllorw'3I](see(ieVisme[4],Wright[:l]alldDriver[1])al,t}(}Inr)1,cdforil](lal[(lllrisl-,i(ital]yarlalyti(:itlI)rooftilt)prim(?number1,if(3or'3m5whi相似文献
11.
Let G be a simple algebraic group defined over an algebraically closed field of characteristic 0 or a good prime for G. Let U be a maximal unipotent subgroup of G and \( \mathfrak{u} \) its Lie algebra. We prove the separability of orbit maps and the connectedness of centralizers for the coadjoint action of U on (certain quotients of) the dual \( \mathfrak{u} \)* of \( \mathfrak{u} \). This leads to a method to give a parametrization of the coadjoint orbits in terms of so-called minimal representatives which form a disjoint union of quasi-affine varieties. Moreover, we obtain an algorithm to explicitly calculate this parametrization which has been used for G of rank at most 8, except E8.When G is defined and split over the field of q elements, for q the power of a good prime for G, this algorithmic parametrization is used to calculate the number k(U(q); \( \mathfrak{u} \)*(q)) of coadjoint orbits of U(q) on \( \mathfrak{u} \)*(q). Since k(U(q), \( \mathfrak{u} \)*(q)) coincides with the number k(U(q)) of conjugacy classes in U(q), these calculations can be viewed as an extension of the results obtained in [11]. In each case considered here there is a polynomial h(t) with integer coefficients such that for every such q we have k(U(q)) = h(q). We also explain implications of our results for a parametrization of the irreducible complex characters of U(q). 相似文献
12.
确定有理数域Q上多项式f(x)的Galois群的阶是一件非常有意义的事情.本文把文献[1]中当m为奇数,多项式f(x)的Galois群的阶确定f(xm)的Galois群的阶的方法,推广到了m为偶时,对f(xm)的条件作进一步限制后,得到相同的结论.同时给出了m=2时,对f(x2)的条件削弱后的相应结论. 相似文献
13.
51.IntroductionSupposethatr>Oisafixednumberand[oldenotes,asusuaI,theintegralpartofo.LetForo1wasfirststudiedin1953byPjateckii-Sapiro[']whoprovedthat(1.1)holdsfor1相似文献
14.
Let G be a π-separable group for a set of primes, let N be a normal subgroup of G, and let θ be an Iπ-character(i.e., irreducible π-partial character) of N. We obtain a necessary and suffcient condition for the number of Iπ-characters of G over θ to take the possible maximum |G : N |π. Some applications are given. 相似文献
15.
本文证明了下面主要结果:设G是n-可解群,π是一些素数之集,若对任意p∈∩π(G),(p,n(1-n))=1,则G的π-Hall子群的个数r=k1k2...kt,每ki≡1(modp),某P∈π,且每ki整除G的一个主因子。 相似文献
16.
17.
《Quaestiones Mathematicae》2013,36(3-4):397-407
Abstract The classical Vitali-Hahn-Saks-Nikodym Theorem [5, Thm. I.4.8] gives a limit criterion for when a sequence of strongly additive vector measures on a σ-field of sets having their range in a Banach space can be expected to be uniformly strongly additive. In [16, Cor. 8], Saeki proved that the limit condition on the sequence of vector measures could be substantially weakened as long as the Banach space in play is “good enough”. Saeki's result was based upon his work on a class of set functions too large to have Rosenthal's Lemma at his disposal. In Section 2, we prove Saeki's result with Rosenthal's Lemma at the basis of our work and then augment our characterization of Banach spaces enjoying Saeki's result in [1] with another natural equivalent condition. In Section 3 we extend Saeki's result to Boolean algebras having the Subsequential Interpolation property. 相似文献
18.
Summary We prove that any doubly transitive permutation group with abelian stabilizers is the group of linear functions over a suitable field. The result is not new: for finite groups it is well known, for infinite groups it follows from a more general theorem of W. Kerby and H. Wefelscheid on sharply doubly transitive groups in which the stabilizers have finite commutator subgroups. We give a direct and elementary proof. 相似文献
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20.
ON F-z-SUPPLEMENTED SUBGROUPS OF FINITE GROUPS 总被引:1,自引:0,他引:1
A subgroup H of a group G is called F-z-supplemented in G if there exists a subgroup K of G, such that G = HK and H∩K≤ Z∞F(G), where Z∞F(G) is the F-hypercenter of G. We obtain some results about the F-z-supplemented subgroups and use them to determine the structure of some groups. 相似文献