CONGRUENCE AND NON-CONGRUENCE SUBGROUPS OF THE (2,3,7)-GROUP
نویسندگان
چکیده
منابع مشابه
Congruence Subgroups of the Modular Group
The congruence subgroups of the classical modular group which can be defined as the automorphs modulo q of some fixed matrix are studied, and their genera determined. Let T = SL{2, Z). A congruence subgroup of T is any subgroup containing a principal congruence subgroup T^), defined as the set of elements A of T such that A = I mod q, where q is a positive integer. Of these one of the most impo...
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ژورنال
عنوان ژورنال: Glasgow Mathematical Journal
سال: 2006
ISSN: 0017-0895,1469-509X
DOI: 10.1017/s0017089506003223