Advanced Graph Theory focuses on some of the main notions arising in graph theory with
an emphasis from the very start of the book on the possible applications of the theory and …

Two finite words u and v are k-binomially equivalent if, for each word x of length at most k, x
appears the same number of times as a subsequence (ie, as a scattered subword) of both u …

Timed languages contain sequences of discrete events (" letters'') separated by real-valued
delays, they can be recognized by timed automata, and represent behaviors of various real …

Let F be a finitely generated free group, and H≤ F a finitely generated subgroup. An
equation for an element g∈ F with coefficients in H is an element w (x)∈ H⁎< x> such that w …

We consider decision problems for relations over finite and infinite words defined by finite
automata. We prove that the equivalence problem for binary deterministic rational relations …

The Fibonacci word f= 010010100100101··· is one of the most well-studied words in the
area of combinatorics on words. It is not periodic, but nevertheless contains many highly …

The bandwidth of timed automata characterizes the quantity of information
produced/transmitted per time unit. We previously delimited 3 classes of TA according to the …

We define a new strict and computable hierarchy for the family of automaton semigroups,
which reflects the various asymptotic behaviors of the state-activity growth. This hierarchy …

Two words u and v are said to be k-abelian equivalent if, for each word x of length at most k,
the number of occurrences of x as a factor of u is the same as for v. We study some …

The hairpin completion is a natural operation on formal languages which has been inspired
by molecular phenomena in biology and by DNA-computing. In 2009 we presented in 6 a …