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Σ12 and Π11 Mad Families

Published online by Cambridge University Press:  12 March 2014

Asger Törnquist*
Affiliation:
Department of Mathematical Sciences, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark, E-mail: asger@logic.univie.ac.at

Abstract

We answer in the affirmative the following question of Jörg Brendle: If there is a Σ21 mad family, is there then a Π11 mad family?

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2009

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References

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