Abstract
We show that the class of groups with k-multiple context-free word problem is closed under graphs of groups with finite edge groups.
Funding source: National Science Foundation
Award Identifier / Grant number: DMS-1440140
Funding statement: This work was started at MSRI, Berkeley, where research is supported by the National Science Foundation under Grant No. DMS-1440140.
Acknowledgements
We greatly thank Bob Gilman for introducing us to the subject and making this project possible. The second author would like to thank UC Berkeley for inviting him as a visiting scholar. The first author would like to thank Alessandro Sisto for inviting him to complete this work at the ETH. We thank the anonymous referee for helpful comments and suggestions, in particular, the addition of Section 6. Finally, we would like to thank Neil Fullarton for his invaluable work with a stapler.
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