Notre Dame Journal of Formal Logic

On Ideals Related to I[λ]

Todd Eisworth


We describe a recipe for generating normal ideals on successors of singular cardinals. We show that these ideals are related to many weakenings of □ that have appeared in the literature. Our main purpose, however, is to provide an organized list of open questions related to these ideals.

Article information

Notre Dame J. Formal Logic, Volume 46, Number 3 (2005), 301-307.

First available in Project Euclid: 30 August 2005

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Digital Object Identifier

Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 03E05: Other combinatorial set theory
Secondary: 03E65: Other hypotheses and axioms

square combinatorial set theory ideals weak squares


Eisworth, Todd. On Ideals Related to I [λ]. Notre Dame J. Formal Logic 46 (2005), no. 3, 301--307. doi:10.1305/ndjfl/1125409328.

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