On some unary algebras and their subalgebra lattices
On subalgebra lattices of a finite unary algebra. I.
One of the main aims of the present and the next part [15] is to show that the theory of graphs (its language and results) can be very useful in algebraic investigations. We characterize, in terms of isomorphisms of some digraphs, all pairs , where is a finite unary algebra and a finite lattice such that the subalgebra lattice of is isomorphic to . Moreover, we find necessary and sufficient conditions for two arbitrary finite unary algebras to have isomorphic subalgebra lattices. We solve...
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 surjective kernels of partial algebras.
On the characterization of primal partial algebras by strong regular hyperidentities.
On the lattice of convex subsets of a partial monounary algebra
On the partial semi-hypergroups with empty diagonal
On the tensor product of a Boolean algebra and an orthoalgebra
Pairwise intersections of Słupecki type maximal partial clones.
Partial Abelian H_u-Monoids
Partial Boolean algebras in a broader sense and Boolean embeddings
Partial monounary algebras with common closed quasi-endomorphisms
Partial monounary algebras with common congruence relations
Partial monounary algebras with common quasi-endomorphisms
Partially-additive monoids
Partielle Algebren in Initialkategorien.
Peano-algebras and quasi-algebras [Book]
Projection representable relations on Menger -semigroups
Abstract characterizations of relations of nonempty intersection, inclusion end equality of domains for partial -place functions are presented. Representations of Menger -semigroups by partial -place functions closed with respect to these relations are investigated.
Pseudocomplements in sum-ordered partial semirings
We study a particular way of introducing pseudocomplementation in ordered semigroups with zero, and characterise the class of those pseudocomplemented semigroups, termed g-semigroups here, that admit a Glivenko type theorem (the pseudocomplements form a Boolean algebra). Some further results are obtained for g-semirings - those sum-ordered partially additive semirings whose multiplicative part is a g-semigroup. In particular, we introduce the notion of a partial Stone semiring and show that several...
Quasi-orders of algebras