Abstract
Exact values are obtained of the n-widths of 2π-periodic functions of the form
in space L2[0, 2π] and satisfy condition
where ω m (φ; t)−mth order modulus of continuity of function φ(x) ∈ L2[0, 2π]. Some further generalizations are included.
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Shabozov, M.S. On widths of periodic functions in L2. Arab. J. Math. 2, 303–312 (2013). https://doi.org/10.1007/s40065-013-0076-z
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DOI: https://doi.org/10.1007/s40065-013-0076-z