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841.
We introduce the notion of -pair of a proper subgroup of a finite group and give necessary and sufficient conditions for supersolvability and nilpotence of a finite group. As application, we give a proof to a recent open problem of Skiba in the unsolved problems in group theory. 相似文献
842.
New classes of domains with explicit Bergman kernel 总被引:9,自引:1,他引:8
Roos GUY 《中国科学A辑(英文版)》2004,47(3):352-371
We introduce two classes of egg type domains, built on general bounded sym-metric domains, for which we obtain the Bergman kernel in explicit formulas. As an aux-iliary tool, we compute the integral of complex powers of the generic norm on a boundedsymmetric domains using the well-known integral of Selberg. This generalizes matrix in-tegrals of Hua and leads to a special polynomial with integer or half-integer coefficientsattached to each irreducible bounded symmetric domain. 相似文献
843.
Ming-baoSun Xiao-pingYang 《应用数学学报(英文版)》2004,20(1):123-132
For a Carnot group G,we establish the relationship between extended mean values and r-convexfunctions which is introduced in this paper,which is a class of inequalities of Hadamard type for r-convexfunction on G. 相似文献
844.
In this paper we describe vanishing and non-vanishing of cohomology of “most” line bundles over Schubert subvarieties of flag
varieties for rank 2 semisimple algebraic groups. 相似文献
845.
The 3-dimensional Heisenberg group H together with its standard sub-Riemannian metric g0 is viewed as the limit of a family of Riemannian manifolds, (H,gu), u>0. For each u>0, we consider some invariant surfaces with constant mean curvature in (H,gu). These surfaces of (H,gu) have very nice limits as u0. We then define the mean curvature of a hypersurface in (H,g0) to be the limit of its mean curvature in (H,gu). We show that in a more general case, this definition is appropriate. Mathematics Subject Classification (2000) Principal 53C17; Secondary 22E25 相似文献
846.
In this paper, we classify the regular embeddings of arc-transitive simple graphs of order pq for any two primes p and q (not necessarily distinct) into orientable surfaces. Our classification is obtained by direct analysis of the structure of arc-regular subgroups (with cyclic vertex-stabilizers) of the automorphism groups of such graphs. This work is independent of the classification of primitive permutation groups of degree p or degree pq for p q and it is also independent of the classification of the arc-transitive graphs of order pq for p q. 相似文献
847.
Wiebke S. Diestelkamp 《Designs, Codes and Cryptography》2004,33(3):187-197
An important question in the construction of orthogonal arrays is what the minimal size of an array is when all other parameters are fixed. In this paper, we will provide a generalization of an inequality developed by Bierbrauer for symmetric orthogonal arrays. We will utilize his algebraic approach to provide an analogous inequality for orthogonal arrays having mixed levels and show that the bound obtained in this fashion is often sharper than Raos bounds. We will also provide a new proof of Raos inequalities for arbitrary orthogonal arrays with mixed levels based on the same method. 相似文献
848.
Let M be an irreducible projective variety, over an algebraically closed field k of characteristic zero, equipped with an action of a connected algebraic group S over k. Let E
G
be a principal G-bundle over M equipped with a lift of the action of S on M, where G is a connected reductive linear algebraic group. Assume that E
G
admits a reduction of structure group to a maximal torus TG. We give a necessary and sufficient condition for the existence of a T-reduction of E
G
which is left invariant by the action of S on E
G
. 相似文献
849.
We study the problem concerning the influence of indices of maximal subgroups of a simple group on the structure of a group. We obtain a characterization property of all finite simple groups. 相似文献
850.
Let G be a locally compact group, and let L1 (G) be the Banachalgebra which is the group algebra of G. We consider a varietyof Banach left L1 (G)-modules over L1 (G), and seek to determineconditions on G that determine when these modules are eitherprojective or injective or flat in the category. The answerstypically involve G being compact or discrete or amenable. Forexample, in the case where G is discrete and 1 < p < ,we find that the module p (G) is injective whenever G is amenable,and that, if it is amenable, then G is pseudo-amenable,a property very close to that of amenability. 2000 MathematicsSubject Classification 46H25, 43A20. 相似文献