Free subgroups in groups of small de ciency
نویسنده
چکیده
The de ciency of a nite group presentation P : h X j R i is def(P) = jXj jRj, the di erence between the numbers of generators and de ning relators. For a given nitely presented group G, the de ciencies of nite presentations for G are bounded above (for example by the torsion free rank of the abelianisation G=G). The de ciency of G, def(G), is the maximum of the de ciencies of all nite presentations of G. The starting point for this paper is the following result of B Baumslag and Pride.
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تاریخ انتشار 1998