On Complete Characterization of Coefficients of A.e. Converging Orthogonal Series
نویسنده
چکیده
We characterize sequences of numbers (an) such that ∑ n≥1 anΦn converges a.e. for any orthonormal system (Φn) in any L2-space. In our criterion, we use the set B = { ∑ m≥n |am| ;n ≥ 1} and its information function hB(t) = − log3(β − α) for t ∈ (α, β], [α, β] ∩B = {α, β}.
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