On McKenzie's method
Let \(A\) be an algebra, for every cardinal \(\lambda\) let \(\lambda^+\) denote the successor cardinal to \(\lambda\) and let \(\kappa(A)\) denote the supremum over all cardinalities \(|S|^+\) where \(S\) runs through all non-trivial subdirectly irreducible algebras belonging to the variety generated by \(A\). An explicit description for a method discovered by McKenzie allowing to construct a finite algebra \(B\) of finite type with \(\kappa(B)= \omega_1\) is given.
scientific article; zbMATH DE number 926948