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On Rough Subgroup of a Group

Xiquan Liang, Dailu Li (2009)

Formalized Mathematics

This article describes a rough subgroup with respect to a normal subgroup of a group, and some properties of the lower and the upper approximations in a group.

On S -quasinormal and c -normal subgroups of a finite group

Shirong Li, Yangming Li (2008)

Czechoslovak Mathematical Journal

Let be a saturated formation containing the class of supersolvable groups and let G be a finite group. The following theorems are presented: (1) G if and only if there is a normal subgroup H such that G / H and every maximal subgroup of all Sylow subgroups of H is either c -normal or S -quasinormally embedded in G . (2) G if and only if there is a normal subgroup H such that G / H and every maximal subgroup of all Sylow subgroups of F * ( H ) , the generalized Fitting subgroup of H , is either c -normal or S -quasinormally...

On small distances of small 2-groups

Natalia Zhukavets (2001)

Commentationes Mathematicae Universitatis Carolinae

The paper reports the results of a search for pairs of groups of order n that can be placed in the distance n 2 / 4 for the case when n { 16 , 32 } . The constructions that are used are of the general character and some of their properties are discussed as well.

On sM-group.

How, Guan Aun (2003)

Bulletin of the Malaysian Mathematical Sciences Society. Second Series

On soluble groups of automorphisms of nonorientable Klein surfaces

G. Gromadzki (1992)

Fundamenta Mathematicae

We classify up to topological type nonorientable bordered Klein surfaces with maximal symmetry and soluble automorphism group provided its solubility degree does not exceed 4. Using this classification we show that a soluble group of automorphisms of a nonorientable Riemann surface of algebraic genus q ≥ 2 has at most 24(q-1) elements and that this bound is sharp for infinitely many values of q.

On solvability of finite groups with some s s -supplemented subgroups

Jiakuan Lu, Yanyan Qiu (2015)

Czechoslovak Mathematical Journal

A subgroup H of a finite group G is said to be s s -supplemented in G if there exists a subgroup K of G such that G = H K and H K is s -permutable in K . In this paper, we first give an example to show that the conjecture in A. A. Heliel’s paper (2014) has negative solutions. Next, we prove that a finite group G is solvable if every subgroup of odd prime order of G is s s -supplemented in G , and that G is solvable if and only if every Sylow subgroup of odd order of G is s s -supplemented in G . These results improve...

On some finite 2-groups in which the derived group has two generators

Elliot Benjamin, Chip Snyder (2023)

Czechoslovak Mathematical Journal

We show that any finite 2-group, whose abelianization has either 4-rank at most 2 or 8-rank 0 and whose commutator subgroup is generated by two elements, is metabelian. We also prove that the minimal order of any 2-group with nonabelian commutator subgroup of 2-rank 2 is 2 12 .

On some metabelian 2-groups and applications I

Abdelmalek Azizi, Abdelkader Zekhnini, Mohammed Taous (2016)

Colloquium Mathematicae

Let G be some metabelian 2-group satisfying the condition G/G’ ≃ ℤ/2ℤ × ℤ/2ℤ × ℤ/2ℤ. In this paper, we construct all the subgroups of G of index 2 or 4, we give the abelianization types of these subgroups and we compute the kernel of the transfer map. Then we apply these results to study the capitulation problem for the 2-ideal classes of some fields k satisfying the condition G a l ( k ( 2 ) / k ) G , where k ( 2 ) is the second Hilbert 2-class field of k.

On some permutable products of supersoluble groups.

Manuel J. Alejandre, A. Ballester-Bolinches, John Cossey, M. C. Pedraza-Aguilera (2004)

Revista Matemática Iberoamericana

It is well known that a group G = AB which is the product of two supersoluble subgroups A and B is not supersoluble in general. Under suitable permutability conditions on A and B, we show that for any minimal normal subgroup N both AN and BN are supersoluble. We then exploit this to establish some sufficient conditions for G to be supersoluble.

On special p -groups

Renza Cortini (1998)

Bollettino dell'Unione Matematica Italiana

In questo lavoro viene data una caratterizzazione di quei p -gruppi nilpotenti di classe due ed esponente p che sono speciali. Vengono inoltre studiate alcune costruzioni, automorfismi e sottogruppi abeliani di p -gruppi speciali.

On subgroups of ZJ type of an F-injector for Fitting classes F between Ep*p and Ep*Sp.

Ana Martínez Pastor (1994)

Publicacions Matemàtiques

Let G be a finite group and p a prime. We consider an F-injector K of G, being F a Fitting class between Ep*p y Ep*Sp, and we study the structure and normality in G of the subgroups ZJ(K) and ZJ*(K), provided that G verifies certain conditions, extending some results of G. Glauberman (A characteristic subgroup of a p-stable group, Canad. J. Math.20(1968), 555-564).

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