Prefix-Recognisable Graphs and Monadic Second-Order Logic
نویسنده
چکیده
We present several characterisations of the class of prefix-recognisable graphs including representations via graph-grammars and MSO-interpretations. The former implies that prefix-recognisable graphs have bounded clique-width; the latter is used to extend this class to arbitrary relational structures. We prove that the prefix-recognisable groups are exactly the context-free groups. Finally, we develop methods to prove that certain structures are not prefix-recognisable and apply them to well-ordered structures.
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