In recent years,a series of papers about cover-avoiding property of subgroups appeared and all the studies were connected with chief factors of a finite group.However,about the cover-avoiding property of subgroups for...In recent years,a series of papers about cover-avoiding property of subgroups appeared and all the studies were connected with chief factors of a finite group.However,about the cover-avoiding property of subgroups for non-chief factor,there is no study up to now.The purpose of this paper is to build the theory.Let A be a subgroup of a finite group G and Σ:G0≤G1≤…≤Gn some subgroup series of G.Suppose that for each pair(K,H) such that K is a maximal subgroup of H and G i 1 K < H G i for some i,either A ∩ H = A ∩ K or AH = AK.Then we say that A is Σ-embedded in G.In this paper,we study the finite groups with given systems of Σ-embedded subgroups.The basic properties of Σ-embedded subgroups are established and some new characterizations of some classes of finite groups are given and some known results are generalized.展开更多
In this paper, We show that the simple K\-3-groups can be characterized by the orders of their maximal abelian subgroups. That is, we have Theorem Let G be a finite group and M a simple K \-3-group. Then ...In this paper, We show that the simple K\-3-groups can be characterized by the orders of their maximal abelian subgroups. That is, we have Theorem Let G be a finite group and M a simple K \-3-group. Then G is isomorphic to M if and only if the set of the orders of the maximal abelian subgoups of G is the same as that of M .展开更多
We introduce and study the minimal inner-Σ-Ω-groups and the minimal outer-Σ-■-groups.Then we give some applications and obtain some interesting results,including characterizations of nilpotent,supersolvable,solvab...We introduce and study the minimal inner-Σ-Ω-groups and the minimal outer-Σ-■-groups.Then we give some applications and obtain some interesting results,including characterizations of nilpotent,supersolvable,solvable,and p-closed groups in terms of the join of two conjugate cyclic subgroups having the same property.展开更多
基金supported by National Natural Science Foundation of China (Grant No.11071229)Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (Grant No.2010T2J12)
文摘In recent years,a series of papers about cover-avoiding property of subgroups appeared and all the studies were connected with chief factors of a finite group.However,about the cover-avoiding property of subgroups for non-chief factor,there is no study up to now.The purpose of this paper is to build the theory.Let A be a subgroup of a finite group G and Σ:G0≤G1≤…≤Gn some subgroup series of G.Suppose that for each pair(K,H) such that K is a maximal subgroup of H and G i 1 K < H G i for some i,either A ∩ H = A ∩ K or AH = AK.Then we say that A is Σ-embedded in G.In this paper,we study the finite groups with given systems of Σ-embedded subgroups.The basic properties of Σ-embedded subgroups are established and some new characterizations of some classes of finite groups are given and some known results are generalized.
文摘In this paper, We show that the simple K\-3-groups can be characterized by the orders of their maximal abelian subgroups. That is, we have Theorem Let G be a finite group and M a simple K \-3-group. Then G is isomorphic to M if and only if the set of the orders of the maximal abelian subgoups of G is the same as that of M .
基金supported by National Natural Science Foundation of China (Grant No.10871032)the Natural Science Foundation of Jiangsu Province (Grant No. BK2008156)
文摘We introduce and study the minimal inner-Σ-Ω-groups and the minimal outer-Σ-■-groups.Then we give some applications and obtain some interesting results,including characterizations of nilpotent,supersolvable,solvable,and p-closed groups in terms of the join of two conjugate cyclic subgroups having the same property.
