Abstract
We show that for every context free language L over some alphabet Σ there effectively exists a test set F, that is a finite subset of L such that, for any pair (g,h) of homomorphisms on Σ*, g(x)=h(x) for each × in F implies g(x)=h(x) for all × in L.
This result is then extended from homomorphisms to deterministic generalized sequential machine mappings defined by machines with uniformly bounded number of states.
This research was supported by the National Sciences and Engineering Council of Canada, under Grant No. A7403.
This paper was written during the first author's visit at the University of Waterloo, Waterloo, Ontario, Canada.
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References
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Albert, J., Culik, K. (1980). Test sets for homomorphism equivalence on context free languages. In: de Bakker, J., van Leeuwen, J. (eds) Automata, Languages and Programming. ICALP 1980. Lecture Notes in Computer Science, vol 85. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-10003-2_55
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DOI: https://doi.org/10.1007/3-540-10003-2_55
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