An Example of Π30-complete Infinitary Rational Relation

Abstract

We give in this paper an example of infinitary rational relation, accepted by a 2-tape Buchi automaton, which is Π30-complete in the Borel hierarchy. Moreover the example of infinitary rational relation given in this paper has a very simple structure and can be easily described by its sections.

Keywords

• Infinitary rational relations
• topological properties
• Borel hierarchy
• Π30-complete set