scholarly journals A Note on Primitive Permutation Groups of Prime Power Degree

2015 ◽  
Vol 2015 ◽  
pp. 1-4
Author(s):  
Qian Cai ◽  
Hua Zhang

Primitive permutation groups of prime power degree are known to be affine type, almost simple type, and product action type. At the present stage finding an explicit classification of primitive groups of affine type seems untractable, while the product action type can usually be reduced to almost simple type. In this paper, we present a short survey of the development of primitive groups of prime power degree, together with a brief description on such groups.

Author(s):  
Timothy C. Burness ◽  
Adam R. Thomas

Abstract Let G be a finite primitive permutation group on a set $$\Omega $$ Ω with non-trivial point stabilizer $$G_{\alpha }$$ G α . We say that G is extremely primitive if $$G_{\alpha }$$ G α acts primitively on each of its orbits in $$\Omega {\setminus } \{\alpha \}$$ Ω \ { α } . In earlier work, Mann, Praeger, and Seress have proved that every extremely primitive group is either almost simple or of affine type and they have classified the affine groups up to the possibility of at most finitely many exceptions. More recently, the almost simple extremely primitive groups have been completely determined. If one assumes Wall’s conjecture on the number of maximal subgroups of almost simple groups, then the results of Mann et al. show that it just remains to eliminate an explicit list of affine groups in order to complete the classification of the extremely primitive groups. Mann et al. have conjectured that none of these affine candidates are extremely primitive and our main result confirms this conjecture.


2019 ◽  
Vol 62 (4) ◽  
pp. 1137-1162
Author(s):  
Alexander Y. Chua ◽  
Michael Giudici ◽  
Luke Morgan

AbstractDolfi, Guralnick, Praeger and Spiga asked whether there exist infinitely many primitive groups of twisted wreath type with non-trivial coprime subdegrees. Here, we settle this question in the affirmative. We construct infinite families of primitive twisted wreath permutation groups with non-trivial coprime subdegrees. In particular, we define a primitive twisted wreath group G(m, q) constructed from the non-abelian simple group PSL(2, q) and a primitive permutation group of diagonal type with socle PSL(2, q)m, and determine many subdegrees for this group. A consequence is that we determine all values of m and q for which G(m, q) has non-trivial coprime subdegrees. In the case where m = 2 and $q\notin \{7,11,29\}$, we obtain a full classification of all pairs of non-trivial coprime subdegrees.


Author(s):  
CAI HENG LI ◽  
GUANG RAO ◽  
SHU JIAO SONG

Abstract Vertex-primitive self-complementary graphs were proved to be affine or in product action by Guralnick et al. [‘On orbital partitions and exceptionality of primitive permutation groups’, Trans. Amer. Math. Soc.356 (2004), 4857–4872]. The product action type is known in some sense. In this paper, we provide a generic construction for the affine case and several families of new self-complementary Cayley graphs are constructed.


1988 ◽  
Vol 103 (2) ◽  
pp. 213-238 ◽  
Author(s):  
John D. Dixon ◽  
Brian Mortimer

Our object is to describe all of the-primitive permutation groups of degree less than 1000 together with some of their significant properties. We think that such a list is of interest in illustrating in concrete form the kinds of primitive groups which arise, in suggesting conjectures about primitive groups, and in settling small exceptional cases which often occur in proofs of theorems about permutation groups. The range that we consider is large enough to allow examples of most of the types of primitive group to appear. Earlier lists (of varying completeness and accuracy) of primitive groups of degree d have been published by: C. Jordan (1872) [21] ford≤ 17, by W. Burnside (1897) [5] ford≤ 8, by Manning (1929) [34–38] ford≤ 15, by C. C. Sims (1970) [45] ford≤ 20, and by B. A. Pogorelev (1980) [42] ford≤ 50. Unpublished lists have also been prepared by C. C. Sims ford≤ 50 and by Mizutani[41] ford≤ 48. Using the classification of finite simple groups which was completed in 1981 we have been able to extend the list much further. Our task has been greatly simplified by the detailed information about many finite simple groups which is available in theAtlas of Finite Groupswhich we will refer to as theAtlas[8].


Author(s):  
Mariapia Moscatiello ◽  
Colva M. Roney-Dougal

AbstractLet G be a permutation group, acting on a set $$\varOmega $$ Ω of size n. A subset $${\mathcal {B}}$$ B of $$\varOmega $$ Ω is a base for G if the pointwise stabilizer $$G_{({\mathcal {B}})}$$ G ( B ) is trivial. Let b(G) be the minimal size of a base for G. A subgroup G of $$\mathrm {Sym}(n)$$ Sym ( n ) is large base if there exist integers m and $$r \ge 1$$ r ≥ 1 such that $${{\,\mathrm{Alt}\,}}(m)^r \unlhd G \le {{\,\mathrm{Sym}\,}}(m)\wr {{\,\mathrm{Sym}\,}}(r)$$ Alt ( m ) r ⊴ G ≤ Sym ( m ) ≀ Sym ( r ) , where the action of $${{\,\mathrm{Sym}\,}}(m)$$ Sym ( m ) is on k-element subsets of $$\{1,\dots ,m\}$$ { 1 , ⋯ , m } and the wreath product acts with product action. In this paper we prove that if G is primitive and not large base, then either G is the Mathieu group $$\mathrm {M}_{24}$$ M 24 in its natural action on 24 points, or $$b(G)\le \lceil \log n\rceil +1$$ b ( G ) ≤ ⌈ log n ⌉ + 1 . Furthermore, we show that there are infinitely many primitive groups G that are not large base for which $$b(G) > \log n + 1$$ b ( G ) > log n + 1 , so our bound is optimal.


10.37236/2549 ◽  
2013 ◽  
Vol 20 (2) ◽  
Author(s):  
Hua Han ◽  
Zaiping Lu

In this paper, we investigate semisymmetric graphs which arise from affine primitive permutation groups. We give a characterization of such graphs, and then construct an infinite family of semisymmetric graphs which contains the Gray graph as the third smallest member. Then, as a consequence, we obtain a factorization,of the complete bipartite graph $K_{p^{sp^t},p^{sp^t}}$ into connected semisymmetric graphs, where $p$ is an prime, $1\le t\le s$ with $s\ge2$ while $p=2$.


2007 ◽  
pp. 18-26
Author(s):  
Dmytro V. Bazyk

At the present stage of scientific research, one of the undefined problems in religious studies is, first of all, the problem of the expediency and relevance of the use of the term "primitive religions" or "primitive religious beliefs" in relation to both representatives of Aboriginal peoples of the present and the analysis of the development of religions in the history of forms of religion. discovered in general. The problem of determining the original religion and its forms of expression is somewhat compounded by the fact that the use of special terminology in theoretical developments depends not only on the various features of research methodological approaches, but also on the language in which studies are commonly published. Therefore, the use of one or the other terminology requires the isolation of a possible synonym for relatively adequate nomination (naming) of these religious manifestations.


2020 ◽  
Vol 24 (4) ◽  
pp. 942-964
Author(s):  
Alexey S. Koshel

The article investigtes the powers and parliamentary procedures in the standing committees and commissions of several countries of Western Europe and Latin America. The author believes that one of the modern paradigms for the development of parliamentary democracy is to strengthen the role of standing committees in the work of parliament by transferring to the committee level a number of constitutional powers of parliaments. In this regard, the author clarifies approaches to the classification of the committee structure of parliaments and looks at committee parliamentary procedures in Italy, Germany, Greece, Portugal, Spain, Brazil and Argentina at the present stage. The author comes to certain conclusions regarding the paradigm of the committee parliamentary procedure, including further improvement of domestic constitutional-legal matter in the context of the ongoing development of parliamentary democracy in the Russian Federation.


1972 ◽  
Vol 9 (6) ◽  
pp. 447-470 ◽  
Author(s):  
W. Misdorp ◽  
E. Cotchin ◽  
J. F. Hampe ◽  
Anne G. Jabara ◽  
J. von Sandersleben

A preliminary classification of 130 canine mammary adenocarcinomas, 76 solid carcinomas, and nine spindle cell carcinomas, together with several subtypes, was constructed from pooled, selected (metastasized) material. Each tumour in this series was classified by subjective assessment of its quantitatively predominant histological picture. Many adenocarcinomas and solid carcinomas of simple type were infiltrative, and lymphatic permeation was often found. The complex types of adenocarcinomas and of solid carcinomas were expansive, and lymphatic permeation was rare. Some metastasized adenocarcinomas were well differentiated. The clinical signs, distribution of metastases and some preliminary data on the times of survival of dogs with various types of carcinomas are discussed.


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