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Proceedings of the American Mathematical Society

Published by the American Mathematical Society, the Proceedings of the American Mathematical Society (PROC) is devoted to research articles of the highest quality in all areas of pure and applied mathematics.

ISSN 1088-6826 (online) ISSN 0002-9939 (print)

The 2020 MCQ for Proceedings of the American Mathematical Society is 0.85.

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How separable is a space? That depends on your set theory!
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by Franklin D. Tall PDF
Proc. Amer. Math. Soc. 46 (1974), 310-314 Request permission


A. Wilansky has raised the question of the productive behaviour of the property of having a countable set, such that each point is a sequential limit point of the set. The set-theoretic consistency and independence of the proposition that this property is preserved by products of ${\aleph _1}$ factors is established.
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Additional Information
  • © Copyright 1974 American Mathematical Society
  • Journal: Proc. Amer. Math. Soc. 46 (1974), 310-314
  • MSC: Primary 54B10; Secondary 54E30
  • DOI:
  • MathSciNet review: 0362188