How many varieties of cylindric algebras are there

Varieties of two-dimensional cylindric algebras II

In [2] we investigated the lattice Λ(Df 2) of all subvarieties of the variety Df2 of two-dimensional diagonal free cylindric algebras. In the present paper we investigate the lattice Λ(CA2) of all subvarieties of the variety CA2 of two-dimensional cylindric algebras. We prove that the cardinality of Λ(CA2) is that of the continuum, give a criterion for a subvariety of CA2 to be locally finite, ...

Varieties of Two-dimensional Cylindric Algebras

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