Über die Axiome Produkt-Abgeschlossener Arithmetischer Klassen

  title={{\"U}ber die Axiome Produkt-Abgeschlossener Arithmetischer Klassen},
  author={Arnold Oberschelp},
  journal={Archiv f{\"u}r mathematische Logik und Grundlagenforschung},
  • Arnold Oberschelp
  • Published 1958
  • Mathematics
  • Archiv für mathematische Logik und Grundlagenforschung
On normal operations on models
Reduced products and Horn classes
Q Ai > el of structures modulo the filter D on I is that homomorphic image of the direct product of i cI which is determined in a certain way by D (see ?2). Chang showed that any Horn class is closedExpand
Properties preserved under algebraic constructions
The study of properties of algebras belongs equally to Algebra and to Metamathematics. But here we consider only questions that concern all abstract algebras, and we attempt to discuss them withoutExpand


Contributions to the theory of models. III
On Sentences Which are True of Direct Unions of Algebras
  • A. Horn
  • Mathematics, Computer Science
  • J. Symb. Log.
  • 1951
A wide class of invariant sentences is determined which are true of a direct union provided they aretrue of some factor algebra and it will be shown that these criteria are the only ones of their kind. Expand
The Decision Problem for Some Classes of Sentences Without Quantifiers
  • J. McKinsey
  • Mathematics, Computer Science
  • J. Symb. Log.
  • 1943
A rather broad sufficient condition for the existence of a decision method for sentences without quantifiers is formulated, and it is shown that this condition holds of lattices. Expand