# Counting and empty alternating pushdown automata ∗

@inproceedings{Reinhardt1992CountingAE, title={Counting and empty alternating pushdown automata ∗}, author={K. Reinhardt}, year={1992} }

We show that the class of context free languages CFL is not equal to ⊕1−PDA (= ⊕CFL), the class of languages, which are recognized by a nondeterministic oneway push-down automaton equipped with parity acceptance. Furthermore we show that LOG(⊕CFL) = ⊕AuxPDApt contains all languages, which can be recognized by a uniform weak unambiguous AC1-circuit introduced in [LR90a]. Therefore, it contains all languages, which can be recognized by a CREW -PRAM. We show, that L#Aux PDApt is contained in… Expand

#### One Citation

Empty Alternation

- Computer Science
- MFCS
- 1994

We introduce the notion of empty alternation by investigating alternating automata which are restricted to empty their storage except for a logarithmically space-bounded tape before making an… Expand

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