Geodesic
On the best mean square approximations by entire functions of exponential type in $L_2(\mathbb R)$ and mean $\nu$-widths of some functional classes
Izvestiâ vysših učebnyh zavedenij. Matematika, no. 7 (2014), pp. 30-48.

Voir la notice de l'article provenant de la source Math-Net.Ru

We consider some extremal problems of approximation theory of functions at the whole real axis $\mathbb R$ by entire functions of the exponential type. In particular, we find the exact values of the mean $\nu$-widths of classes of functions, defined by the moduli of continuity of $m$th order $\omega_m$ and majorants $\Psi$ satisfying the special type of restriction.
Keywords: best approximation, entire function of exponential type, modulus of continuity, mean $\nu$-width
Mots-clés : majorant. 
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     title = {On the best mean square approximations by entire functions of exponential type in $L_2(\mathbb R)$ and mean $\nu$-widths of some functional classes},
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S. B. Vakarchuk; M. Sh. Shabozov; M. R. Langarshoev. On the best mean square approximations by entire functions of exponential type in $L_2(\mathbb R)$ and mean $\nu$-widths of some functional classes. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 7 (2014), pp. 30-48. http://geodesic.mathdoc.fr/item/IVM_2014_7_a2/

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