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Rooted trees, strong cofinality and ample generics

Published online by Cambridge University Press:  01 October 2012

MACIEJ MALICKI*
Affiliation:
Institute of Mathematics, Polish Academy of Sciences, Sniadeckich 8, 00-956, Warsaw, Poland, and Lazarski University, Swieradowska 43, 02-662, Warsaw, Poland. e-mail: mamalicki@gmail.com

Abstract

We characterize those countable rooted trees with non-trivial components whose full automorphism group has uncountable strong cofinality, and those whose full automorphism group contains an open subgroup with ample generics.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2012

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References

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