ITA
2008
13 years 4 months ago
2008
A set T L is a Parikh test set of L iff c(T ) is a test set of c(L). We give an effective characterization of Parikh test sets for arbitrary commutative language.
ITA
2008
13 years 4 months ago
2008
ITA
2008
13 years 4 months ago
2008
The complexity of infinite words is considered from the point of view of a transformation with a Mealy machine that is the simplest model of a finite automaton transducer. We are ...
ITA
2008
13 years 4 months ago
2008
The necessary and sufficient conditions are extracted for periodicity of bi-ideals. By the way two proper subclasses of uniformly recurrent words are introduced.
ITA
2008
13 years 4 months ago
2008
A language L A is literally idempotent in case that ua2 v L if and only if uav L, for each u, v A , a A. Varieties of literally idempotent languages result naturally by taking...
ITA
2008
13 years 4 months ago
2008
ITA
2008
13 years 4 months ago
2008
We prove that there exists a structure M whose monadic second order theory is decidable, and such that the elementary theory of every expansion of M by a constant is undecidable. 1...
ITA
2008
13 years 4 months ago
2008
ITA
2008
13 years 4 months ago
2008
We prove two cases of a strong version of Dejean's conjecture involving extremal letter frequencies. The results are that there exist an infinite " 5 4 + " -free wor...
ITA
2008
13 years 4 months ago
2008
In this article, we study the complexity of drunken man infinite words. We show that these infinite words, generated by a deterministic and complete countable automaton, or equival...