Abstract. We consider a formalisation of a notion of observer (or intruder) theories, commonly used in symbolic analysis of security protocols. An observer theory describes the kno...
Abstract. Intuitively, a recursion theorem asserts the existence of selfreferential programs. Two well-known recursion theorems are Kleene’s Recursion Theorem (krt) and Rogers’...
Abstract. In answer-set programming (ASP), many notions of program equivalence have been introduced and formally analysed. A particular line of research in this direction aims at s...
Abstract. Nested words are a restriction of the class of visibly pushdown languages that provide a natural model of runs of programs with recursive procedure calls. The usual conne...
Abstract. The recently proposed notion of an elementary set yielded a refinement of the theorem on loop formulas, telling us that the stable models of a disjunctive logic program ...