covering monolithic groups with proper subgroups

نویسندگان

martino garonzi

چکیده

‎given a finite non-cyclic group $g$‎, ‎call $sigma(g)$ the smallest number of proper subgroups of $g$ needed to cover $g$‎. ‎lucchini and detomi conjectured that if a nonabelian group $g$ is such that $sigma(g) < sigma(g/n)$ for every non-trivial normal subgroup $n$ of $g$ then $g$ is textit{monolithic}‎, ‎meaning that it admits a unique minimal normal subgroup‎. ‎in this paper we show how this conjecture can be attacked by the direct study of monolithic groups‎.

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عنوان ژورنال:
international journal of group theory

ناشر: university of isfahan

ISSN 2251-7650

دوره 2

شماره 1 2013

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