سال انتشار: ۱۳۸۶

محل انتشار: سی و هشتمین کنفرانس ریاضی ایران

تعداد صفحات: ۳

نویسنده(ها):

SEYYED MAJID JAFARIAN AMIRI – Department of Methematics, Faculty of Sciences, University of Zanjan, Iran

چکیده:

A cover for a group G is a collection of its proper subgroups whose union is the whole group G. Cohn defined σ(G) to be the least integer m such that G is the union of m proper subgroups. Determining σ is an open problem for most non-solveble groups. We obtion σ(G) for some primitive groups.