We generalize the cardinal
invariant a to products of 𝒫(ω)∕fin and then sharpen the well-known inequality
b ≤ a by proving b ≤ a(λ) for every λ ≤ ω. Here a(n), for n < ω, is the least size of
an infinite partition of (𝒫(ω)∕fin)n, a(ω) is the least size of an uncountable partition
of (𝒫(ω)∕fin)ω, and b is the least size of an unbounded family of functions from ω to
ω ordered by eventual dominance. We also prove the consistency of b < a(n) for
every n < ω.
Mathematisches Seminar,
Mathematisch-Naturwissenschaftliche Fakultät
Christian-Albrechts-Universität zu Kiel
Raum: 516
Ludewig-Meyn-Str. 4
D-24118 Kiel
Germany