Sparse sets, tally sets, and polynomial reducibilities -- Functional programming and combinatory algebras -- On models and algebras for concurrent processes -- String matching with constraints -- Structure of complexity classes: Separations, collapses, and completeness -- Inductive syntactical synthesis of programs from sample computations -- 3-dimensional shortest paths in the presence of polyhedral obstacles -- Robust oracle machines -- Recognizable sets with multiplicities in the tropical semiring -- Reusable specification components -- Comparing interconnection networks -- Probabilistic automata complexity of languages depends on language structure and error probability -- Breadth-first phrase structure grammars and queue automata -- Implementing abstract data structures in hardware -- Distribution of Sequential Processes -- Automata and rational expressions on planar graphs -- On maximal prefix sets of words -- Infinite behaviour of deterministic petri nets -- Testing isomorphism of outerplanar graphs in parallel -- Efficient simulations between concurrent-read concurrent-write pram models -- Multiple propositional dynamic logic of parallel programs -- The steiner tree problem and homogeneous sets -- Termination of rewriting is undecidable in the one-rvle case -- Local checking of trace synchronizability -- Edge separators for planar graphs and their applications -- A fast parallel algorithm for eigenvalue problem of jacobi matrices -- Strong and robustly strong polynomial time reducibilities to sparse sets -- Context-free-like forms for the phrase-structure grammars -- On the expressive strength of the finitely typed lambda — terms -- Hoare calculi for higher — type control siructures and their completeness in the sense of cook -- On representing CCS programs by finite petri nets -- A taxonomy of fairness and temporal logic problems for petri nets -- Branching programs as a tool for proving lower bounds on vlsi computations and optimal algorithms for systolic arrays -- Two lower bounds for circuits over the basis (&, V, -) -- Positive/Negative conditional rewriting -- On the computational complexity of codes in graphs -- Separating the eraser turing machine classes Le, NLe, co-NLe and Pe -- Compositional proofs by partial specification of processes -- Introducing negative information in relational databases -- On positive occur-checks in unification -- Two applications of fürer's counter to one-tape nondeterministic TMs -- ? 2 p -complete lexicographically first maximal subgraph problems -- Proof system for weakest prespecification and its applications -- On complexity of counting -- Design, proof and analysis of new efficient algorithms for incremental attribute evaluation -- On efficiency of interval routing algorithms -- An almost linear robinson unification algorithm -- Random boolean formulas representing any boolean function with asymptotically equal probability -- On the power of communication in alternating machines -- Classes of cnf-formulas with backtracking trees of exponential or linear average order for exact-satisfiability -- Bisections of free monoids and a new unavoidable regularity -- Failures semantics and deadlocking of modular petri nets -- A decomposition theorem for finite-valued transducers and an application to the equivalence problem.

This volume contains 11 invited lectures and 42 communications presented at the 13th Conference on Mathematical Foundations of Computer Science, MFCS '88, held at Carlsbad, Czechoslovakia, August 29 - September 2, 1988. Most of the papers present material from the following four fields: - complexity theory, in particular structural complexity, - concurrency and parellelism, - formal language theory, - semantics. Other areas treated in the proceedings include functional programming, inductive syntactical synthesis, unification algorithms, relational databases and incremental attribute evaluation.