Alexandr Kazda

Learn More
Alexandr Kazda The chain relation in sofic subshifts Introduction Characterisation of the chain relation Summary Outline 1 Introduction Shifts and subshifts The chain relation 2 Characterisation of the chain relation Linking graph Theorem about chain relation Corollaries Alexandr Kazda The chain relation in sofic subshifts Introduction Characterisation of(More)
We study the complexity of computation in finitely generated free left, right and two-sided adequate semigroups and monoids. We present polynomial time (quadratic in the RAM model of computation) algorithms to solve the word problem and compute normal forms in each of these, and hence also to test whether any given identity holds in the classes of left,(More)
Möbius number systems represent points using sequences of Möbius transformations. Thorough the paper, we are mainly interested in representing the unit circle (which is equivalent to representing R ∪ {∞}). The main aim of the paper is to improve already known tools for proving that a given subshift–iterative system pair is in fact a Möbius number system. We(More)
The main result of this paper is a generalization of the classical blossom algorithm for finding perfect matchings. Our algorithm can efficiently solve Boolean CSPs where each variable appears in exactly two constraints (we call it edge CSP) and all constraints are even ∆-matroid relations (represented by lists of tuples). As a consequence of this, we(More)
Möbius number systems represent the extended real line or, equivalently, the unit complex circle by sequences of Möbius transformations. A Möbius number system consists of an iterative system of Möbius transformations and a subshift. In this paper we give an overview of the area of Möbius number systems. We are particularly interested in the conditions,(More)
We characterize absorption in finite idempotent algebras by means of Jónsson absorption and cube term blockers. As an application we show that it is decidable whether a given subset is an absorbing subuniverse of an algebra given by the tables of its basic operations.