Covering relation in the language of mono-unary algebras with at most one constant symbol (Q1121932)

A description of the lattice of equational theories for a language with just one unary operation symbol and arbitrarily many constants was given by Jezek. In the case of a unary operation symbol and at most one constant the author presents effective procedures for finding the theories which are covered by \(\theta\) [E] and the theories which cover \(\theta\) [E], where \(\theta\) [E] is the theory generated by a finite set E of equations.