SOME SUBGROUPS OF THE EXTENDED HECKE GROUPS H^－（λq）  

作　　者：ReeepSahin OsmanBizim 

机构地区：[1]DepartmentofMathematics,FacultyofArtsandSciences,BalikesirUniversity,10100Balikesir/TURKEY [2]DepartmentofMathematics,FacultyofArtsandSciences,UludayUniversity,16059Bursa/TURKEY

出　　处：《Acta Mathematica Scientia》2003年第4期497-502,共6页数学物理学报（B辑英文版）

摘　　要：The authors consider the extended Hecke groups H(γq) generated by T(z) = -1 / z, S(z) = -1(z +γq) and R(z) = 1 / z with A, = 2 cos(π/q) for q≥3 an integer. In this paper, the even subgroup He(γq), the second commutator subgroup H''(γq) and the principal congruence subgroups Hp(λq) of the extended Hecke groups .H(γq) are studied. Also, relations between them are given.The authors consider the extended Hecke groups H(γq) generated by T(z) = -1 / z, S(z) = -1(z +γq) and R(z) = 1 / z with A, = 2 cos(π/q) for q≥3 an integer. In this paper, the even subgroup He(γq), the second commutator subgroup H''(γq) and the principal congruence subgroups Hp(λq) of the extended Hecke groups .H(γq) are studied. Also, relations between them are given.

关 键 词：Extended Hecke group even subgroup commutator subgroup principal congruence subgroup 

分 类 号：O152[理学—数学]