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Tree self-embeddings

Published online by Cambridge University Press:  20 November 2018

David Ross*
Affiliation:
Department of Pure Mathematics, University of Hull, Hull, HU6 7RX, England
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Abstract

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Elementary proofs are given of the following two statements: (1) Every infinite tree of height at most ω properly embeds into itself. (2) There is a tree of height ω + 1 that does not properly embed into itself.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1989

References

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