We compute the cardinality of the syntactic monoid of the language 0∗ repb(mN) made of base b expansions of the multiples of the integer m. We also give lower bounds for the syntactic complexity of any (ultimately) periodic set of integers written in base b. We apply our results to a well studied problem: decide whether or not a b-recognizable set of integers is ultimately periodic.

We consider combinatorial and algebraic properties of the language of factors of the in+nite sequence on the three-letter alphabet built by S.E. Arshon in 1930s. This sequence never contains two successive equal words, i. e., avoids the number 2. The notion of avoidability is extended from integers to rational numbers. It is shown that the avoidability bound for the considered language is 4 . T...

The syntactic complexity of a tree language is defined according to the number of the distinct syntactic classes of all trees with a fixed yield length. This leads to a syntactic classification of tree languages and it turns out that the class of recognizable tree languages is properly contained in that of languages with bounded complexity. A refined syntactic complexity notion is also presente...

The advantages of tabled evaluation regarding program termination and reduction of complexity are well known —as are the significant implementation, portability, and maintenance efforts that some proposals (especially those based on suspension) require. This implementation effort is reduced by program transformation-based continuation call techniques, at some efficiency cost. However, the tradi...

This paper explores what children and adults know about three specific ways that meaning and context interact: the interpretation of expressions whose extensions vary in different contexts (semantic context dependence); conditions on the felicitous use of expressions in a discourse context (presupposition accommodation) and informative uses of expressions in contexts in which they strictly spea...

To establish lower bounds on the amount of replication, there is a common partition argument used to construct indistinguishable executions such that one violates some property of interest. This violation leads to the conclusion that the lower bound on process replication is of the form n > bkt/bc, where t is the maximum number of process failures in any of these executions and k, b are positiv...

We extend the Kripke-like model theory given in 10] for a fragment of rst-order hereditary Harrop formulae to include negated atoms in goals. This gives us a formal framework in which to study the role of Negation as Failure rule. The class of predicates for which Negation As Failure is applicable is discussed, as well as the predicates for which some other form of negation will need to be used...

News agencies and other news providers or consumers are confronted with the task of extracting events from news articles. This is done i) either to monitor and, hence, to be informed about events of specific kinds over time and/or ii) to react to events immediately. In the past, several promising approaches to extracting events from text have been proposed. Besides purely statistically-based ap...

The syntactic semigroup problem is to decide whether a given finite semigroup is syntactic or not. This work investigates the syntactic semigroup problem for both the semigroup reducts of A(Bn), the affine nearsemiring over a Brandt semigroup Bn. It is ascertained that both the semigroup reducts of A(Bn) are syntactic semigroups.

Abduction is usually carried out on partially-defined predicates. In this paper we investigate abduction applied to fully-defined predicates, specifically linear arithmetic constraints over the real numbers. Abduction in this context has application to query answering using views and type inference, and potential relevance to analysis of concurrent/constraint/logic programs. We show that only r...