N ov 2 00 8 Compressed word problems in HNN - extensions and amalgamated products
نویسنده
چکیده
It is shown that the compressed word problem for an HNNextension 〈H, t | tat = φ(a)(a ∈ A)〉 with A finite is polynomial time Turing-reducible to the compressed word problem for the base group H . An analogous result for amalgamated free products is shown as well.
منابع مشابه
. G R ] 1 N ov 2 00 4 RELATIVE DEHN FUNCTIONS OF AMALGAMATED PRODUCTS AND HNN – EXTENSIONS
We obtain an upper bound for relative Dehn functions of amalgamated products and HNN–extensions with respect to certain collections of subgroups. Our main results generalize the combination theorems for relatively hyperbolic groups proved by Dahmani.
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