2 papers
math.LO2026
On omega-powers of infinite difference rank
Maxim Vishnikin
It is proved that there exists a language such that its -power has infinite rank in the difference hierarchy of open sets. The same holds for the decreasing difference hiera…
math.LO2025
Categorial grammars with unique category assignment
Maxim Vishnikin, Alexander Okhotin
A categorial grammar assigns one of several syntactic categories to each symbol of the alphabet, and the category of a string is then deduced from the categories assigned to its sy…