This article is cited in 2 papers

Undecidability of Elementary Theories of Rogers Semilattices on Limit Levels of Hyperarithmetical Hierarchy

N. A. Baklanova

Novosibirsk State University

Abstract: Proved that elementary theory of any non-trivial Rogers semilattice in hyperarithmetical hierarchy is undecidable.

Keywords: numbering, Rogers semilattice, hyperarithmetical hierarchy, minimal elements, minimal covers.

UDC: 510.5

Received: 25.02.2011