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

Published electronically:
February 27, 2003

MathSciNet review:
1975392

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Abstract | References | Similar Articles | Additional Information

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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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

Keywords:
Maximal almost-disjoint families,
almost-disjointness number,
iterated forcing.

Received by editor(s):
October 3, 2001

Published electronically:
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