Piecewise testable tree languages

Mikołaj Bojańczyk (1) , Luc Segoufin (2) , Howard Straubing (3)

1 MIMUW - Faculty of Mathematics, Informatics, and Mechanics [Warsaw]
2 DAHU - Verification in databases
3 BC - Boston College

This paper presents a decidable characterization of tree languages that can be defined by a boolean combination of Σ1 sentences. This is a tree extension of the Simon theorem, which says that a string language can be defined by a boolean combination of Σ1 sentences if and only if its syntactic monoid is J-trivial.

Domaines: Informatique et langage [cs.CL]

Mikołaj Bojańczyk, Luc Segoufin, Howard Straubing. Piecewise testable tree languages. Logical Methods in Computer Science, 2012, 8 (3), pp.29. ⟨hal-01160458⟩