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Variations on ◊

Published online by Cambridge University Press:  12 March 2014

Keith J. Devlin*
Affiliation:
University of Lancaster, Lancaster LA1 4YL, England

Abstract

Various equivalents and weakenings of the combinatorial principle ◊ are considered. The paper contains both absolute results and consistency results. Also included is a new characterisation of the notion of a stationary subset of ω1.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1979

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References

REFERENCES

[1]Devlin, K. J., Aspects of constructibility, Lecture Notes in Mathematics, no. 354, Springer-Verlag, Berlin and New York, 1973.Google Scholar
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