On some varieties of weakly associative lattice groups
On spectral continuity of positive elements
Let x be a positive element of an ordered Banach algebra. We prove a relationship between the spectra of x and of certain positive elements y for which either xy ≤ yx or yx ≤ xy. Furthermore, we show that the spectral radius is continuous at x, considered as an element of the set of all positive elements y ≥ x such that either xy ≤ yx or yx ≤ xy. We also show that the property ϱ(x + y) ≤ ϱ(x) + ϱ(y) of the spectral radius ϱ can be obtained for positive elements y which satisfy at least one of the...
On Stanley-Reisner rings
On strictly positive lattice ordered semigroups
On strong semimodular lattices III
On strong superlattices
On strong uniform dimension of locally finite groups
We give the description of locally finite groups with strongly balanced subgroup lattices and we prove that the strong uniform dimension of such groups exists. Moreover we show how to determine this dimension.
On structural properties of normality relations on lattices
On subalgebra lattices of a finite unary algebra. II.
We use graph-algebraic results proved in [8] and some results of the graph theory to characterize all pairs of lattices for which there is a finite partial unary algebra such that its weak and strong subalgebra lattices are isomorphic to and , respectively. Next, we describe other pairs of subalgebra lattices (weak and relative, etc.) of a finite unary algebra. Finally, necessary and sufficient conditions are found for quadruples of lattices for which there is a finite unary algebra having...
On subdirectly irreducible lattice-ordered semigroups .
On subdirectly irreducible ordered semigroups.
On summability in convergence -groups
On sums over partially ordered sets.
On system of subobject functors in the category of ordered sets
On systems of congruences on principal filters of orthomodular implication algebras
Orthomodular implication algebras (with or without compatibility condition) are a natural generalization of Abbott’s implication algebras, an implication reduct of the classical propositional logic. In the paper deductive systems (= congruence kernels) of such algebras are described by means of their restrictions to principal filters having the structure of orthomodular lattices.
On systems of overlapping sets and symmetric polynomial inequalities
On Tabor's problem concerning a certain quasi-ordering of iterative roots of functions.
On ternary semigroups of homomorphisms of ordered sets
The paper deals with the characterization of ordered sets by means of ternary semigroups of homomorphisms of ordered sets.
On the additive semigroup of ordered semirings.
On the additive semigroup structure of semirings.