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AML
2006
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13 years 4 months ago
There is no ordering on the classes in the generalized high/low hierarchies
We prove that the existential theory of the Turing degrees, in the language with Turing reduction, 0, and unary relations for the classes in the generalized high/low hierarchy, is ...
Antonio Montalbán
FSTTCS
2003
Springer
13 years 10 months ago
Word Equations over Graph Products
For monoids that satisfy a weak cancellation condition, it is shown that the decidability of the existential theory of word equations is preserved under graph products. Furthermore...
Volker Diekert, Markus Lohrey