On the Norm Convergence of Nonconventional Ergodic Averages
نویسنده
چکیده
We offer a proof of the following nonconventional ergodic theorem: Theorem. If Ti : Z y (X,Σ, μ) for i = 1, 2, . . . , d are commuting probability-preserving Z-actions, (IN )N≥1 is a Følner sequence of subsets of Z, (aN )N≥1 is a base-point sequence in Z and f1, f2, . . . , fd ∈ L∞(μ) then the nonconventional ergodic averages
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