# A Very Hard log-Space Counting Class

@article{lvarez1993AVH, title={A Very Hard log-Space Counting Class}, author={C. {\`A}lvarez and Birgit Jenner}, journal={Theor. Comput. Sci.}, year={1993}, volume={107}, pages={3-30} }

Abstract We consider the logarithmic-space counting and optimization classes #L, span-L, and opt-L, which are defined analogously to their polynomial-time counterparts. We obtain complete functions for these three classes in terms of graphs and finite automata. We show that #L and opt-L are both included in NC 2 , but that, surprisingly, span-L seems to be a much harder class than #L and opt-L. We demonstrate that span-L functions can be computed in polynomial time if and only if P (#P) and all… Expand

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