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621.
设G是2-(v,k,1)设计D上的自同构群的一个子群,且是线-本原.如果(V,k)=k/k2,k2≤10.则G也是点-本原的。  相似文献   
622.
本文在凸六角系统分类的基础上给出了它的自同构群有完美匹配存在的充要冬件和计数函数的不定方程。  相似文献   
623.
624.
主要研究区传递2-(v,k,1)设计的分类.特别地,考虑了非可解区传递2-(v,7,1)设计的分类,得到了如下结论:设G是一2-(v,7,1)设计(£)的自同构群,若G区传递非可解且点本原,但非旗传递地作用在设计D上,则G≠PSLn(q),这里q为奇数且(n,q)≠(2,2),(2,3).  相似文献   
625.
The partial quadrangle PQ(s, t, μ) is an incidence system consisting of points and lines in which every line contains s + 1 points, every point sits on t + 1 lines (two lines meet in at most one point), and the meet of the neighborhoods of any two non-adjacent points in the collinearity graph is a μ-coclique. We provide a classification for partial quadrangles PQ(s, t, μ) with t ⩽ 6, and study into their automorphisms. Supported by RFBR grant No. 05-01-00046 and by RFBR-NSFC grant No. 05-01-39000. __________ Translated from Algebra i Logika, Vol. 45, No. 5, pp. 603–619, September–October, 2006.  相似文献   
626.
The automorphism groups of algebras are found in many papers. Using auto-invariance, we find the automorphism groups of the Laurent extension of the polynomial ring and the quantum n-plane (respectively, twisting polynomial ring) in this work. As an application of the results of this work, we can find the automorphism group of a twisting algebra. We define a generalized Weyl algebra and show that the generalized Weyl algebra is simple. We also find the automorphism group of a generalized Weyl algebra. We show that the generalized Weyl algebra A m,m+n is the universal enveloping algebra of the generalized Witt algebra W(m,m + n). This work was supported by 2007 Research fund of Hanyang University  相似文献   
627.
TheNewSeriesofLA-Groups(Ⅰ)班桂宁,李世余,张劲松TheNewSeriesofLA-Groups(Ⅰ)¥Bangining;LiShiyu;ZhangJinsong(MathsDept.,GuangXiUniversity,N...  相似文献   
628.
A scheme of construction of infinite groups, other than simplegroups, free groups of infinite rank and the infinite cyclicgroup, which are isomorphic to all their non-trivial normalsubgroups is presented. Some results about the automorphismgroups of simple infinite groups are also obtained. In particular,it is proved that there is an infinite group G of any sufficientlylarge prime exponent p (or which is torsion-free) all of whoseproper subgroups are cyclic, and such that the groups Aut Gand Out G are isomorphic. The proofs use the technique of gradeddiagrams developed by A. Yu. Ol'shanskii. 1991 Mathematics SubjectClassification: 20F05, 20F06.  相似文献   
629.
A connected graph of girth m 3 is called a polygonal graph if it contains a set of m-gons such that every path of length two is contained in a unique element of the set. In this paper we investigate polygonal graphs of girth 6 or more having automorphism groups which are transitive on the vertices and such that the vertex stabilizers are 3-homogeneous on adjacent vertices. We previously showed that the study of such graphs divides naturally into a number of substantial subcases. Here we analyze one of these cases and characterize the k-valent polygonal graphs of girth 6 which have automorphism groups transitive on vertices, which preserve the set of special hexagons, and which have a suborbit of size k – 1 at distance three from a given vertex.  相似文献   
630.
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