Ascending Hnn - Extensions and Properly 3 - Realisable Groups
نویسنده
چکیده
The most useful constructions in Combinatorial Group Theory are amalgamated free products and HNN-extensions, and they are the two basic examples in the theory of graphs of groups due to Bass and Serre (see [9]). We recall that given a group G and a subgroup H 6 G together with monomorphisms (respectively homomorphisms) ψ, φ : H −→ G, the group determined by the presentation 〈 G, t; t−1ψ(h)t = φ(h), h ∈ H 〉
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تاریخ انتشار 2006