Retract irreducibility of monounary algebras
Retract varieties of lattice ordered groups
Retract varieties of monounary algebras
Retracts and monomorphism monoids in semigroup varieties.
Retracts and Q-independence
A non-empty set X of a carrier A of an algebra A is called Q-independent if the equality of two term functions f and g of the algebra A on any finite system of elements a₁,a₂,...,aₙ of X implies f(p(a₁),p(a₂),...,p(aₙ)) = g(p(a₁),p(a₂),...,p(aₙ)) for any mapping p ∈ Q. An algebra B is a retract of A if B is the image of a retraction (i.e. of an idempotent endomorphism of B). We investigate Q-independent subsets of algebras which have a retraction in their set of term functions.
Retracts of monounary algebras corresponding to groupoids
Rigid Boolean Algebras
Ring varieties closed under ideal sums
Ring-like operations is pseudocomplemented semilattices
Ring-like operations are introduced in pseudocomplemented semilattices in such a way that in the case of Boolean pseudocomplemented semilattices one obtains the corresponding Boolean ring operations. Properties of these ring-like operations are derived and a characterization of Boolean pseudocomplemented semilattices in terms of these operations is given. Finally, ideals in the ring-like structures are defined and characterized.
Ring-like structures corresponding to generalized orthomodular lattices
Root decomposition of the ternary Mal'tsev algebra .
Rough subalgebras of some binary algebras connected with logics.