Let G be a finite group.The question how the properties of its minimal subgroups influence the structure of G is of considerable interest for some scholars.In this paper we try to use c-normal condition on minimal sub...Let G be a finite group.The question how the properties of its minimal subgroups influence the structure of G is of considerable interest for some scholars.In this paper we try to use c-normal condition on minimal subgroups to characterize the structure of G.Some previously known results are generalized.展开更多
Let F be a saturated formation containing the class of supersolvable groups and let G be a finite group. The following theorems are shown： （1） G ∈ F if and only if there is a normal subgroup H such that G/H ∈ F a...Let F be a saturated formation containing the class of supersolvable groups and let G be a finite group. The following theorems are shown： （1） G ∈ F if and only if there is a normal subgroup H such that G/H ∈ F and every maximal subgroup of all Sylow subgroups of H is either c-normal or s-quasinormally embedded in G; （2） G ∈F if and only if there is a soluble normal subgroup H such that G/H∈F and every maximal subgroup of all Sylow subgroups of F（H）, the Fitting subgroup of H, is either e-normally or s-quasinormally embedded in G.展开更多
An operator T on a separable,infinite dimensional,complex Hilbert space H is called conjugate normal if C|T|C=|T^(*)| for some conjugate linear,isometric involution C on H.This paper focuses on the invariance of conju...An operator T on a separable,infinite dimensional,complex Hilbert space H is called conjugate normal if C|T|C=|T^(*)| for some conjugate linear,isometric involution C on H.This paper focuses on the invariance of conjugate normality under similarity.Given an operator T,we prove that every operator A similar to T is conjugate normal if and only if there exist complex numbersλ_(1),λ_(2)such that(T-λ_(1))(T-λ_(2))=0.展开更多
Let G be a finite group. A subgroup H of G is called an H-subgroup in G if NG（H）∩ H^g ≤ H for all g C G. A subgroup H of G is called a weakly H-subgroup in G if there exists a normal subgroup K of G such that G = ...Let G be a finite group. A subgroup H of G is called an H-subgroup in G if NG（H）∩ H^g ≤ H for all g C G. A subgroup H of G is called a weakly H-subgroup in G if there exists a normal subgroup K of G such that G = HK and H N K is an H-subgroup in G. In this paper, we investigate the structure of the finite group G under the assumption that every subgroup of G of prime order or of order 4 is a weakly H-subgroup in G. Our results improve and generalize several recent results in the literature.展开更多
基金The author is supported in part by NSF of China and NSF of Guangdong Province
文摘Let G be a finite group.The question how the properties of its minimal subgroups influence the structure of G is of considerable interest for some scholars.In this paper we try to use c-normal condition on minimal subgroups to characterize the structure of G.Some previously known results are generalized.
基金the Natural Science Foundation of Chinathe Natural Science Foundation of Guangxi Autonomous Region (No.0249001)
文摘Let F be a saturated formation containing the class of supersolvable groups and let G be a finite group. The following theorems are shown： （1） G ∈ F if and only if there is a normal subgroup H such that G/H ∈ F and every maximal subgroup of all Sylow subgroups of H is either c-normal or s-quasinormally embedded in G; （2） G ∈F if and only if there is a soluble normal subgroup H such that G/H∈F and every maximal subgroup of all Sylow subgroups of F（H）, the Fitting subgroup of H, is either e-normally or s-quasinormally embedded in G.
基金supported by the National Natural Science Foundation of China (Grant No.12171195).
文摘An operator T on a separable,infinite dimensional,complex Hilbert space H is called conjugate normal if C|T|C=|T^(*)| for some conjugate linear,isometric involution C on H.This paper focuses on the invariance of conjugate normality under similarity.Given an operator T,we prove that every operator A similar to T is conjugate normal if and only if there exist complex numbersλ_(1),λ_(2)such that(T-λ_(1))(T-λ_(2))=0.
基金supported by the Deanship of Scientific Research(DSR) at King Abdulaziz University(KAU) represented by the Unit of Research Groups through the grant number(MG/31/01) for the group entitled "Abstract Algebra and its Applications"
文摘Let G be a finite group. A subgroup H of G is called an H-subgroup in G if NG（H）∩ H^g ≤ H for all g C G. A subgroup H of G is called a weakly H-subgroup in G if there exists a normal subgroup K of G such that G = HK and H N K is an H-subgroup in G. In this paper, we investigate the structure of the finite group G under the assumption that every subgroup of G of prime order or of order 4 is a weakly H-subgroup in G. Our results improve and generalize several recent results in the literature.
