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Remarks on partition ordinals

Conference paper
Part of the Lecture Notes in Mathematics book series (LNM, volume 1401)

Abstract

After a brief survey of the theory of partition ordinals, i.e., ordinals α such that α → (α,n)2 for all n < ω, it is shown that MA(ℵ1) implies that ω1ω and ω1ω2 are partition ordinals. This contrasts with an old result of Erdős and Hajnal that α ↛ (α,3)2 holds for both these ordinals under the Continuum Hypothesis.

Keywords

Order Type Dartmouth College Doubling Property Complete Subgraph Hereditary Property 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  1. 1.Dartmouth CollegeHanoverUSA

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