Abstract
For even values of n we find the exact values of the diameters dn(W(r)Hω) of the classes of 2π-periodic functions (Ω(t) is an arbitrary convex upwards modulus of continuity) in the space C2π. We find that d2n(W(r)Hω)=d2n−1(W(r)Hω) (n=1, 2, ... r=0, 1, 2, ...).
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Translated from Matematicheskie Zametki, Vol. 15, No. 3, pp. 387–392, March, 1974.
The author expresses his thanks to N. P. Korneichuk for his interest in my work.
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Ruban, V.I. Even diameters of the classes W(r)H ω in the space C2π . Mathematical Notes of the Academy of Sciences of the USSR 15, 222–225 (1974). https://doi.org/10.1007/BF01438374
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DOI: https://doi.org/10.1007/BF01438374