Some cardinal characteristics related to the covering number and the uniformity of the meagre ideal

Nattapon Sonpanow,

Pimpen Vejjajiva


We extend the concepts of splitting, reaping, and independent families to families of functions and permutations on ω and define associated cardinal characteristics sf , sp, rf , rp, if , and ip. We study relationships among cov(M), non(M), and these cardinals. In this paper, we show that sf = non(M) = sp, rf = cov(M) ≤ rp, and cov(M) ≤ if , ip.

AMS subject classification: 03E17.

Słowa kluczowe: cardinal characteristic, covering number, uniformity

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