Strong meager properties for filters

نویسنده

C. Laflamme

چکیده

We analyze several “strong meager” properties for filters on the natural numbers between the classical Baire property and a filter being Fσ . Two such properties have been studied by Talagrand and a few more combinatorial ones are investigated. In particular, we define the notion of a P+-filter, a generalization of the traditional concept of P-filter, and prove the existence of a non-meager P+-filter. Our motivation lies in understanding the structure of filters generated by complements of members of a maximal almost disjoint family.

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