Knapsack in Graph Groups, HNN-Extensions and Amalgamated Products
It is shown that the knapsack problem, which was introduced by Myasnikov et al. for arbitrary finitely generated groups, can be solved in NP for graph groups. This result even holds if the group elements are represented in a compressed form by SLPs, which generalizes the classical NP-completeness result of the integer knapsack problem. We also prove general transfer results: NP-membership of the knapsack problem is passed on to finite extensions, HNN-extensions over finite associated subgroups, and amalgamated products with finite identified subgroups.
Graph groups
HNN-extensions
amalgamated products
knapsack
50:1-50:14
Regular Paper
Markus
Lohrey
Markus Lohrey
Georg
Zetzsche
Georg Zetzsche
10.4230/LIPIcs.STACS.2016.50
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