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Finding paths through narrow and wide trees

Published online by Cambridge University Press:  12 March 2014

Stephen Binns
Affiliation:
Department of Mathematics and Statistics, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia, E-mail: binns@kfupm.edu.sa
Bjørn Kjos-Hanssen
Affiliation:
Department of Mathematics, University of Hawai‘i at Mānoa, Honolulu, Hi 96822, USA, E-mail: bjoern@math.hawaii.edu

Abstract

We consider two axioms of second-order arithmetic. These axioms assert, in two different ways, that infinite but narrow binary trees always have infinite paths. We show that both axioms are strictly weaker than Weak König's Lemma, and incomparable in strength to the dual statement (WWKL) that wide binary trees have paths.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2009

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References

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