Hardness results for isomorphism and automorphism of bounded valence graphs
نویسنده
چکیده
In a bounded valence graph every vertex has O(1) neighbours. Testing isomorphism of bounded valence graphs is known to be in P [15], something that is not clear to hold for graph isomorphism in general. We show that testing isomorphism for undirected, directed and colored graphs of valence 2 is logspace complete. We also prove the following: If a special version of bounded valence GI is hard for ModkL then it is also hard for #L. All results are proved with respect to DLOGTIME uniform AC many-one reductions.
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