摘要
确定了广义超特殊p-群G的自同构群的结构.设|G|=p^(2n+m),|■G|=p^m,其中n≥1,m≥2,Aut_fG是AutG中平凡地作用在Frat G上的元素形成的正规子群,则(1)当G的幂指数是p^m时,(i)如果p是奇素数,那么AutG/AutfG≌Z_((p-1)p^(m-2)),并且AutfG/InnG≌Sp(2n,p)×Zp.(ii)如果p=2,那么AutG=Aut_fG(若m=2)或者AutG/AutfG≌Z_(2^(m-3))×Z_2(若m≥3),并且AutfG/InnG≌Sp(2n,2)×Z_2.(2)当G的幂指数是p^(m+1)时,(i)如果p是奇素数,那么AutG=〈θ〉■Aut_fG,其中θ的阶是(p-1)p^(m-1),且Aut_f G/Inn G≌K■Sp(2n-2,p),其中K是p^(2n-1)阶超特殊p-群.(ii)如果p=2,那么AutG=〈θ_1,θ_2〉■Aut_fG,其中〈θ_1,θ_2〉=〈θ_1〉×〈θ_2〉≌Z_(2^(m-2))×Z_2,并且Aut_fG/Inn G≌K×Sp(2n-2,2),其中K是2^(2n-1)阶初等Abel 2-群.特别地,当n=1时,AutfG/InnG≌Zp.
In this paper,the automorphism group of a generalized extraspecial p-group G is determined,where p is a prime number.Assume that |G|= p^(2n+m) and |ξG| = p^m,where n≥1 and m≥2.Let AutfG be the normal subgroup of Aut G consisting of all elements of Aut G which act trivially on Prat G.Then (1) When the exponent of G is equal to p^m, (i) If p is odd,then Aut G/AutfG≌Z((p-1)p^(m-2)) and AutfG/Inn G≌Sp(2n,p)×Zp. (ii) If p = 2,then Aut G = AutfG(when m = 2) or Aut G/AutfG≌Z(2^(m-3))×Z2(when m≥3),and AutfG/Inn G≌Sp(2n,2)×Z2. (2) When the exponent of G is equal to p^(m+1), (i) If p is odd,then Aut G = θAutfG,whereθis of order(p-1)p^(m-1),and AutfG/InnG≌K Sp(2n - 2,p),where K is an extraspecial p-group of order p^(2n-1). (ii) If p = 2,then Aut G = θ1,θ2 AutfG,where θ1,θ2 = θ1×θ2≌Z(2^(m-2))×Z2, and AutfG/Inn G≌K Sp(2n-2,2),where K is an elementary abelian 2-group of order 2^(2n-1). In particular,AutfG/Inn G≌Zp when n = 1.
出处
《数学年刊(A辑)》
CSCD
北大核心
2011年第3期307-318,共12页
Chinese Annals of Mathematics
基金
国家自然科学基金(No.10971054)
河南省教育厅自然科学基金(No.2011B110011)
河南工业大学科研基金(No.10XZZ011)
河南工业大学引进人才专项基金(No.2009BS029)资助的项目
关键词
广义超特殊p-群
中心积
辛群
自同构
Generalized extraspecial p-group
Central product
Symplectic group
Automorphism