مرور International Journal of Group Theory بر اساس تاریخ انتشار
در حال نمایش موارد 1 - 20 از 259
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The exact spread of M23 is 8064
(University of Isfahan, 2012-03-01)Let $G$ be a finite group. We say that $G$ has emph{spread} r if for any set of distinct non-trivial elements of $G$ $X:={x_1,ldots, x_r}subset G^{#}$ there exists an element $yin G$ with the property that $langle ...
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On the relation between the non-commuting graph and the prime graph
(University of Isfahan, 2012-03-01)$pi(G)$ denote the set of prime divisors of the order of $G$ and denote by $Z(G)$ the center of $G$. Thetextit{ prime graph} of $G$ is the graph with vertex set $pi(G)$ where two distinct primes $p$ and $q$ are ...
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Some remarks on regular subgroups of the affine group
(University of Isfahan, 2012-03-01)Let $V$ be a vector space over a field $F$ of characteristic $pgeq 0$ and let $T$ be a regular subgroup of the affine group $AGL(V)$. In the finite dimensional case we show that, if $T$ is abelian or $p>0$, then ...
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Locally finite p-groups with all subgroups either subnormal or nilpotent-by-Chernikov
(University of Isfahan, 2012-03-01)We pursue further our investigation, begun in [H. Smith, Groups with all subgroups subnormal or nilpotent-by-Chernikov, Rend. Sem. Mat. Univ. Padova, 126 (2011), ...
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Refined solvable presentations for polycyclic groups
(University of Isfahan, 2012-06-01)We describe a new type of presentation that, when consistent, describes a polycyclic group. This presentation is obtained by refining a series of normal subgroups with abelian sections. These presentations can ...
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The prolongation of central extensions
(University of Isfahan, 2012-06-01)The aim of this paper is to study the $(alpha, gamma)$-prolongation of central extensions. We obtain the obstruction theory for $(alpha, gamma)$-prolongations and classify $(alpha, gamma)$-prolongations thanks to ...
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The automorphism group for $p$-central $p$-groups
(University of Isfahan, 2012-06-01)A $p$-group $G$ is $p$-central if $G^{p}le Z(G)$, and $G$ is $p^{2}$-abelian if $(xy)^{p^{2}}=x^{p^{2}}y^{p^{2}}$ for all $x,yin G$. We prove that for $G$ a finite $p^{2}$-abelian $p$-central $p$-group, excluding ...
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Groups with reality and conjugacy conditions
(University of Isfahan, 2012-06-01)Many results were proved on the structure of finite groups with some restrictions on their real elements and on their conjugacy classes. We generalize a few of these to some classes of infinite groups. We study ...
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On varietal capability of Infinite direct products of groups
(University of Isfahan, 2012-09-01)Recently, the authors gave some conditions under which a direct product of finitely many groups is $mathcal{V}-$capable if and only if each of its factors is $mathcal{V}-$capable for some varieties $mathcal{V}$. In ...
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On the semi cover-avoiding property and $mathcal{F}$-supplementation
(University of Isfahan, 2012-09-01)In this paper, we investigate the influence of some subgroups of Sylow subgroups with semi cover-avoiding property and $mathcal{F}$-supplementation on the structure of finite groups and generalize a series of known results.
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Infinite groups with many generalized normal subgroups
(University of Isfahan, 2012-09-01)A subgroup $X$ of a group $G$ is almost normal if the index $|G:N_G(X)|$ is finite, while $X$ is nearly normal if it has finite index in the normal closure $X^G$. This paper investigates the structure of groups in which ...
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Quasirecognition by prime graph of $U_3(q)$ where $2 < q =p^{alpha} < 100$
(University of Isfahan, 2012-09-01)Let $G $ be a finite group and let $Gamma(G)$ be the prime graph of G. Assume $2
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A new characterization of $PSL(2, 25)$
(University of Isfahan, 2012-09-01)Let $G$ be a finite group and $pi_{e}(G)$ be the set of element orders of $G$. Let $k in pi_{e}(G)$ and $m_{k}$ be the number of elements of order $k$ in $G$. Set nse($G$):=${ m_{k} | k in pi_{e}(G)}$. In this ...
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On finite A-perfect abelian groups
(University of Isfahan, 2012-09-01)Let $G$ be a group and $A=Aut(G)$ be the group of automorphisms of $G$. Then the element $[g,alpha]=g^{-1}alpha(g)$ is an autocommutator of $gin G$ and $alphain A$. Also, the autocommutator subgroup of G is ...
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On Graham Higman's famous PORC paper
(University of Isfahan, 2012-12-01)We investigate Graham Higman's paper Enumerating $p$-groups, II, in which he formulated his famous PORC conjecture. We are able to simplify some of the theory. In particular, Higman's paper ...
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Fischer matrices of Dempwolff group $2^{5}{^{cdot}}GL(5,2)$
(University of Isfahan, 2012-12-01)In [U. Dempwolff, On extensions of elementary abelian groups of order $2^{5}$ by $GL(5,2)$, Rend. Sem. Mat. Univ. Padova, 48 (1972) 359 - 364.] Dempwolff proved the existence ...
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Finite simple groups with number of zeros slightly greater than the number of nonlinear irreducible characters
(University of Isfahan, 2012-12-01)The aim of this paper is to classify the finite simple groups with the number of zeros at most seven greater than the number of nonlinear irreducible characters in the character tables. We find that they are exactly ...
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CH-groups which are finite $p$-groups
(University of Isfahan, 2012-12-01)In their paper "Finite groups whose noncentral commuting elements have centralizers of equal size", S. Dolfi, M. Herzog and E. Jabara classify the groups in question- which they call $ CH$-groups- up ...
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Proceedings of Ischia Group Theory 2012
(University of Isfahan, 2013-03-01)Proceedings of Ischia Group Theory 2012
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On the representation theory of the alternating groups
(University of Isfahan, 2013-03-01)We present the basic results on the representation theory of the alternating groups $A_n$. Our approach is based on Clifford theory.
