Article
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

A subgroup A is called seminormal in a group G if there exists a subgroup B such that G = AB and AX is a subgroup of G for every subgroup X of B. Studying a group of the form G = AB with seminormal supersoluble subgroups A and B, we prove that GU=(G)NG^{\mathfrak{U}}=\left(G^{\prime}\right)^{\mathfrak{N}}. Moreover, if the indices of the subgroups A and B of G are coprime then GU=(GN)2G^{\mathfrak{U}}=\left(G^{\mathfrak{N}}\right)^{2}. Here N\mathfrak{N}, U\mathfrak{U}, and N2\mathfrak{N}^2 are the formations of all nilpotent, supersoluble, and metanilpotent groups respectively, while HXH^{\mathfrak{X}} is the X\mathfrak{X}-residual of H. We also prove the supersolubility of G = AB when all Sylow subgroups of A and B are seminormal in G.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... The groups G = AB with seminormal supersoluble subgroups A and B were investigated in [5]. It is established that G U = (G ) N [5,Theorem 2.3]. ...
... The groups G = AB with seminormal supersoluble subgroups A and B were investigated in [5]. It is established that G U = (G ) N [5,Theorem 2.3]. The supersolubility of G = AB is also proved provided that all Sylow subgroups of A and B are seminormal in G [5,Theorem 2.4]. ...
... It is established that G U = (G ) N [5,Theorem 2.3]. The supersolubility of G = AB is also proved provided that all Sylow subgroups of A and B are seminormal in G [5,Theorem 2.4]. ...
Article
Let G be a group. A subgroup H is weakly subnormal in G if H=A,B H=\langle A,B\rangle for some subnormal subgroup A and seminormal subgroup B in G . Note that B is seminormal in G if there exists a subgroup Y such that G=BY and AX is a subgroup for every subgroup X in Y . We give some new properties of weakly subnormal subgroups and new information about the structure of the group G=AB with weakly subnormal subgroups A and B . In particular, we prove that if A,BF A,B\in\mathfrak{F} , then GF(G)N G^{\mathfrak{F}}\leq(G^{\prime})^{\mathfrak{N}} , where F \mathfrak{F} is a saturated formation such that UF \mathfrak{U}\subseteq\mathfrak{F} . Here N \mathfrak{N} and U \mathfrak{U} are the formations of all nilpotent and supersoluble groups correspondingly, and GF G^{\mathfrak{F}} is the F {\mathfrak{F}} -residual of G . Moreover, we study the groups G=AB whose Sylow (maximal) subgroups from A and B are weakly subnormal in G .
... The factorizable groups G = AB with w-supersoluble factors A and B were investigated in [8], [10], [11], [14]. There are many other papers devoted to study factorizable groups, and the reader is referred to the book [1] and the bibliography therein. ...
Preprint
Let P\Bbb P be the set of all primes. A subgroup H of a group G is called {\it P\mathbb P-subnormal} in G, if either H=G, or there exists a chain of subgroups H=H0H1Hn=G, Hi:Hi1P, i.H=H_0\le H_1\le \ldots \le H_n=G, \ |H_{i}:H_{i-1}|\in \Bbb P, \ \forall i. A group G is called {\it widely supersoluble}, w\mathrm{w}-supersoluble for short, if every Sylow subgroup of G is P\mathbb P-subnormal in G. A group G=AB with P\mathbb P-subnormal w\mathrm{w}-supersoluble subgroups A and B is studied. The structure of its w\mathrm{w}-supersoluble residual is obtained. In particular, it coincides with the nilpotent residual of the A\mathcal{A}-residual of G. Here A\mathcal{A} is the formation of all groups with abelian Sylow subgroups. Besides, we obtain new sufficient conditions for the w\mathrm{w}-supersolubility of such group G.
Article
A subgroup A is seminormal in a finite group G if there exists a subgroup B such that G = AB and AX is a subgroup for each subgroup X from B. We study a group G = G1G2 . . .Gn with pairwise permutable supersolvable groups G1, . . . ,Gn such that Gi and Gj are seminormal in GiGj for any i, j ∈ {1, . . . , n}, i ≠ j. It is stated that GU = (G')N. Here N and U are the formations of all nilpotent and supersolvable groups, and HX and H' are the X-residual and the derived subgroup, respectively, of a group H. It is proved that a group G = G1G2 . . .Gn with pairwise permutable subgroups G1, . . .,Gn is supersolvable provided that all Sylow subgroups of Gi and Gj are seminormal in GiGj for any i, j ∈ {1, . . . , n}, i ≠ j.
Article
Let P be the set of all primes. A subgroup H of G is called P-subnormal in G, if either H = G, or there exists a chain H=H0≤H1≤…≤Hn=G,|Hi:Hi−1|∈P,∀i. Recall that G is w-supersoluble, if every Sylow subgroup of G is P-subnormal in G. The structure of w-supersoluble residual of G = AB with P-subnormal w-supersoluble subgroups A and B is obtained.
Article
Full-text available
We study finite groups in which each primary subgroup is self-normalizing or U\mathfrak{U}-subnormal in the class U of all supersoluble groups. In particular, these groups have a Sylow tower.
Book
Full-text available
The study of finite groups factorised as a product of two or more subgroups has become a subject of great interest during the last years with applications not only in group theory, but also in other areas like cryptography and coding theory. It has experienced a big impulse with the introduction of some permutability conditions. The aim of this book is to gather, order, and examine part of this material, including the latest advances made, give some new approach to some topics, and present some new subjects of research in the theory of finite factorised groups.
Article
Full-text available
Tests for π-solvability of a finite group with seminormal Hall π-subgroup are established and the nilpotency of the third commutator subgroup of any group with seminormal noncyclic Sylow subgroups is proved.
Article
Full-text available
A non-nilpotent finite group whose proper subgroups are all nilpotent is called a Schmidt group. A subgroup A is said to be seminormal in a group G if there exists a subgroup B such that G = AB and AB1 is a proper subgroup of G, for every proper subgroup B1 of B. Groups that contain seminormal Schmidt subgroups of even order are considered. In particular, we prove that a finite group is solvable if all Schmidt {2, 3}-subgroups and all 5-closed {2, 5}-Schmidt subgroups of the group are seminormal; the classification of finite groups is not used in so doing. Examples of groups are furnished which show that no one of the requirements imposed on the groups is unnecessary.
Article
Let G be a finite group. In this paper we obtain some sufficient conditions for the supersolubility of G with two supersoluble non-conjugate subgroups H and K of prime index, not necessarily distinct. It is established that the supersoluble residual of such a group coincides with the nilpotent residual of the derived subgroup. We prove that G is supersoluble in the following cases: one of the subgroups H or K is nilpotent; the derived subgroup {G^{\prime}} of G is nilpotent; {|G:H|=q>r=|G:K|} and H is normal in G . Also the supersolubility of G with two non-conjugate maximal subgroups M and V is obtained in the following cases: all Sylow subgroups of M and of V are seminormal in G ; all maximal subgroups of M and of V are seminormal in G .
Article
Let H and T be subgroups of a group G. Then we call H conditionally permutable (or in brevity, c-permutable) with T in G if there exists an element x ∈ G such that HT x = T x H. If H is c-permutable with T in < H, T >, then we call H completely c-permutable with T in G. By using the above concepts, we will give some new criterions for the supersolubility of a finite group G = AB, where A and B are both supersoluble groups. In particular, we prove that a finite group G is supersoluble if and only if G = AB, where both A, B are nilpotent subgroups of the group G and B is completely c-permutable in G with every term in some chief series of A. We will also give some applications of our new criterions.
Article
Let H and T be subgroups of a group G. Then we call H conditionally permutable (or in brevity, c-permutable) with T in G if there exists an element x ∈ G such that HT x = T x H. If H is c-permutable with T in < H, T >, then we call H completely c-permutable with T in G. By using the above concepts, we will give some new criterions for the supersolubility of a finite group G = AB, where A and B are both supersoluble groups. In particular, we prove that a finite group G is supersoluble if and only if G = AB, where both A, B are nilpotent subgroups of the group G and B is completely c-permutable in G with every term in some chief series of A. We will also give some applications of our new criterions.
Article
We give a sufficient condition for supersolubility of a finite group that is a product of two subnormal supersoluble subgroups. We prove that the supersoluble residual of such a group is equal to its nilpotent residual. Also we apply these results to finite groups that are a product of two subnormal p-supersoluble subgroups.
Article
This paper identifies a certain class of supersoluble groups (called finitely generated hallsiding groups) which contains the finitely generated nilpotent groups, the metacyclic and the finitely generated soluble T-groups. The main result states that the product of a normal finitely generated hallsiding subgroup and a subnormal supersoluble subgroup is always supersoluble. Some results about products of normal locally supersoluble subgroups are also given. 1991 Mathematics Subject Classification: 20F16, 20E25.
Article
Let H and T be subgroups of a finite group G. We say that H is completely c-permutable with T in G if there exists an element x ∈ 〈H,T〉 such that HTx = TxH. In this paper, we use this concept to determine the supersolubility of a group G = AB, where A and B are supersoluble subgroups of G. Some criterions of supersolubility of such groups are obtained and some known results are generalized. © 2009 Academy of Mathematics and Systems Science, Chinese Academy of Sciences, and Suzhou University.
Article
We prove a variant of Kegel-Wielandt’s theorem. We use this to give some solvability criteria for factorizable finite groups.
Article
Two subgroups X and Y of a group G are said to be conditionally permutable in G if X permutes with Yg for some element g∈G, i.e., XYg is a subgroup of G. Using this permutability property new criteria for the product of finite supersoluble groups to be supersoluble are obtained and previous results are recovered. Also the behaviour of the supersoluble residual in products of finite groups is studied.
Article
In this paper, we prove the following theorem: Let p be a prime number, P a Sylow p-subgroup of a group G and π = π(G) \ {p}. If P is seminormal in G, then the following statements hold: 1) G is a p-soluble group and P′ ≤ Op (G); 2) lp (G) ≤ 2 and lπ (G) ≤ 2; 3) if a π-Hall subgroup of G is q-supersoluble for some q π, then G is q-supersoluble. © 2008 Institute of Mathematics, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Chinese Mathematical Society and Springer-Verlag GmbH.
Article
Eine wichtige Aufgabe der Darstellungstheorie ist die Aufstellung eines vollstandigen Systems von inäquivalenten irreduziblen Darstellungen einer endlichen Gruppe Obwohl man Verfahren kennt, die dies theoretisch leisten (etwa die Reduktion der regularen Darstellung), ist die praktische Durchführung nur in wenigen Fallen möglich. Die Aufgabe vereinfacht sich jedoch wesentlich, wenn sich alle irreduziblen Darstellungen von auf monomiale Gestalt transfor-mieren lassen; denti alle monomialen Darstellungen einer endlichen Gruppe kann man nach einem sehr einfachen Verfahren gewinnen (siehe [4], S. 140).
Seminormal subgroups and supersolubility of finite groups,” Vests
On the p-supersolvability of a finite factorizable group with normal factors
  • V S Monakhov
  • I K Chirik
Трофимук Теорема 3.2. Пусть A и B полунормальные p-сверхразрешимые под-группы p-разрешимой группы G и G = AB. Если коммутант G p-нильпотентен
  • С Монахов
С. Монахов, А. А. Трофимук Теорема 3.2. Пусть A и B полунормальные p-сверхразрешимые под-группы p-разрешимой группы G и G = AB. Если коммутант G p-нильпотентен, то G p-сверхразрешима.
Полунормальные подгруппы и сверхразрешимость конечных групп // Изв. НАН Беларуси. Сер. физ.-мат. наук
  • В В Подгорная
Подгорная В. В. Полунормальные подгруппы и сверхразрешимость конечных групп // Изв. НАН Беларуси. Сер. физ.-мат. наук.. 2000. № 4. С. 22-25.
Конечные группы с полунормальными подгруппами Шмидта // Алгебра и логика
  • В Н Княгина
  • В С Монахов
Княгина В. Н., Монахов В. С. Конечные группы с полунормальными подгруппами Шмидта // Алгебра и логика. 2007. Т. 46, № 4. С. 448-458.
Endliche Gruppen I. Berlin; Heidelberg
  • B Huppert
Huppert B. Endliche Gruppen I. Berlin; Heidelberg; New York: Springer-Verl., 1967.
О сверхразрешимом корадикале произведения субнормальных сверхразрешимых подгрупп // Сиб. мат. журн
  • В С Монахов
  • И К Чирик
Монахов В. С., Чирик И. К. О сверхразрешимом корадикале произведения субнормальных сверхразрешимых подгрупп // Сиб. мат. журн.. 2017. Т. 58, № 2. С. 353-364.
Конечные группы с абнормальными и U-субнормальными подгруппами // Сиб. мат. журн. . 2016. Т. 57, № 2
  • В С Монахов
Монахов В. С. Конечные группы с абнормальными и U-субнормальными подгруппами // Сиб. мат. журн.. 2016. Т. 57, № 2. С. 447-462.
Введение в теорию конечных групп и их классов. Минск: Выш. школа
  • В С Монахов
Монахов В. С. Введение в теорию конечных групп и их классов. Минск: Выш. школа, 2006.
О p-сверхразрешимости конечной факторизуемой группы с нормальными сомножителями // Тр. Ин-та математики и механики УрО РАН
  • В С Монахов
  • И К Чирик
Монахов В. С., Чирик И. К. О p-сверхразрешимости конечной факторизуемой группы с нормальными сомножителями // Тр. Ин-та математики и механики УрО РАН. 2015. Т. 21, № 3. С. 256-267.