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Tagged with ho.history-overview context-free
2 questions
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Why is the Pumping Lemma sometimes called Bar-Hillel's Lemma?
There are several papers in the literature that refer to the Pumping Lemma for context free languages as Bar-Hillel's Lemma (for example, here, here, and on the Wikipedia page). However, the first ...
- 319
12
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Reference for Dyck languages being $\mathsf{TC}_0$-complete
Dyck languages $\mathsf{Dyck}(k)$ is defined by the following grammar
$$
S \rightarrow SS \,|\, (_1 S )_1 \,|\, \ldots \,|\, (_k S )_k \,|\, \epsilon
$$
over the set of symbols $\{(_1,\ldots,(_k,)_1,\...
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