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Now showing items 1-10 of 23

#### Quotient Complexity of Ideal Languages

(Elsevier, 2013-01-28)

A language L over an alphabet Σ is a right (left) ideal if it satisfies L=LΣ∗ (L=Σ∗L). It is a two-sided ideal if L=Σ∗LΣ∗, and an all-sided ideal if L=Σ∗L, the shuffle of Σ∗ with L. Ideal languages are not only of interest ...

#### Syntactic Complexities of Six Classes of Star-Free Languages

(Otto-von-Guericke-Universit¨at Magdeburg, 2012)

The syntactic complexity of a regular language is the cardinality of its syntactic semi-group. The syntactic complexity of a subclass of regular languages is the maximal syntactic complexity of languages in that subclass, ...

#### Most Complex Regular Ideal Languages

(Discrete Mathematics and Theoretical Computer Science, 2016-10-17)

A right ideal (left ideal, two-sided ideal) is a non-empty language $L$ over an alphabet $\Sigma$ such that $L=L\Sigma^*$ ($L=\Sigma^*L$, $L=\Sigma^*L\Sigma^*$). Let $k=3$ for right ideals, 4 for left ideals and 5 for ...

#### Syntactic Complexity of Regular Ideals

(Springer, 2017-08-04)

The state complexity of a regular language is the number of states in a minimal deterministic finite automaton accepting the language. The syntactic complexity of a regular language is the cardinality of its syntactic ...

#### Complexity of Suffix-Free Regular Languages

(Elsevier, 2017-11-01)

We study various complexity properties of suffix-free regular languages. A sequence (Lk,Lk+1,…) of regular languages in some class, where n is the quotient complexity of Ln, is most complex if its languages Ln meet the ...

#### Unrestricted State Complexity Of Binary Operations On Regular And Ideal Languages

(Institut für Informatik, 2017-08-27)

We study the state complexity of binary operations on regular languages over diﬀerent alphabets. It is known that if L′m and Ln are languages of state complexities m and n, respectively, and restricted to the same alphabet, ...

#### Syntactic Complexity of Suffix-Free Languages

(Elsevier, 2017-09-05)

We solve an open problem concerning syntactic complexity: We prove that the cardinality of the syntactic semigroup of a suffix-free language with n left quotients (that is, with state complexity n) is at most (n−1)n−2+n−2 ...

#### Most Complex Non-returning Regular Languages

(Springer, 2017-07-03)

A regular language L is non-returning if in the minimal deterministic finite automaton accepting it there are no transitions into the initial state. Eom, Han and Jirásková derived upper bounds on the state complexity of ...

#### Complexity of Left-Ideal, Suffix-Closed and Suffix-Free Regular Languages

(Springer, 2017-03-06)

A language L over an alphabet Σ is suffix-convex if, for any words x,y,z∈Σ∗, whenever z and xyz are in L, then so is yz. Suffix-convex languages include three special cases: left-ideal, suffix-closed, and suffix-free ...

#### Complexity of Proper Prefix-Convex Regular Languages

(Springer, 2017-06-27)

A language L over an alphabet Σ is prefix-convex if, for any words x,y,z∈Σ∗, whenever x and xyz are in L, then so is xy. Prefix-convex languages include right-ideal, prefix-closed, and prefix-free languages, which were ...