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The almost-disjointness number may have countable cofinality
Author:
Jörg Brendle
Journal:
Trans. Amer. Math. Soc. 355 (2003), 2633-2649
MSC (2000):
Primary 03E17; Secondary 03E35
Posted:
February 27, 2003
MathSciNet review:
1975392
Full-text PDF Free Access
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Abstract: We show that it is consistent for the almost-disjointness number  to have countable cofinality. For example, it may be equal to  .
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- J. Brendle, Mad families and iteration theory, in: Logic and Algebra (Y. Zhang, ed.), Contemp. Math. 302 (2002), Amer. Math. Soc., Providence, RI, 1-31.
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Additional Information
Jörg Brendle
Affiliation:
The Graduate School of Science and Technology, Kobe University, Rokko–dai 1–1, Nada–ku, Kobe 657–8501, Japan
Email:
brendle@kurt.scitec.kobe-u.ac.jp
DOI:
http://dx.doi.org/10.1090/S0002-9947-03-03271-9
PII:
S 0002-9947(03)03271-9
Keywords:
Maximal almost-disjoint families,
almost-disjointness number,
iterated forcing.
Received by editor(s):
October 3, 2001
Posted:
February 27, 2003
Additional Notes:
Supported by Grant–in–Aid for Scientific Research (C)(2)12640124, Japan Society for the Promotion of Science
Article copyright:
© Copyright 2003 American Mathematical Society
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