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Compactness and ordinals

Published online by Cambridge University Press:  18 May 2009

C. J. Knight
Affiliation:
The University, Sheffield, 10
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If p and q are cardinal numbers and E is a topological space, then the following property may or may not hold:

Every cover of Eby fewer than q open sets has a subcover by fewer than pof them. (1)

Clearly these properties, for various numbers p and q, are far from being independent; in this paper, we investigate some of the interrelationships between them.

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 1972

References

REFERENCES

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