Linear Context-Free Tree Languages and Inverse Homomorphisms
Research output: Contribution to journal › Conference article › Contributed › peer-review
Contributors
Abstract
We prove that the class of linear context-free tree languages is not closed under inverse linear tree homomorphisms. In fact, we prove a stronger result: we encode Dyck words into a linear context-free tree language and prove that its preimage under a certain linear tree homomorphism cannot be generated by any context-free tree grammar. A positive result can still be obtained: the linear monadic context-free tree languages are closed under inverse linear tree homomorphisms.
Details
Original language | English |
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Article number | 104454 |
Journal | Information and Computation |
Volume | 269 |
Publication status | Published - 2019 |
Peer-reviewed | Yes |
External IDs
Scopus | 85071551102 |
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Keywords
Keywords
- context-free tree grammars, homomorphisms