Finite algebras of relations are representable on finite sets

H. Andréka, I. Hodkinson, I. Németi

J. Symbolic Logic, to appear.

Using a combinatorial theorem of Herwig on extending partial isomorphisms of relational structures, we give a simple proof that certain classes of algebras, including Crs, polyadic Crs, and WA, have the `finite base property' and have decidable universal theories, and that any finite algebra in each class is representable on a finite set. These results were first established by Andréka and Németi.

Here is a ps.gz file of the paper.

Reference: Bernhard Herwig, Extending partial isomorphisms for the small index property of many (omega)-categorical structures, 1996, currently (Jan 97) available here.