On functions with bounded $\mathbf n$th differences

Yu. V. Kryakin

Izvestiya. Mathematics , Tome 61 (1997) no. 2, pp. 331-346.

Résumé

Modified Whitney constants for approximation by cubic polynomials are calculated exactly. New estimates are obtained of Whitney constants for approximating $C(I^N)$-functions by quasi-polynomials.

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