## Hermite-Birkhoff interpolation in the $n$th roots of unity

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- by A. S. Cavaretta, A. Sharma and R. S. Varga PDF
- Trans. Amer. Math. Soc.
**259**(1980), 621-628 Request permission

## Abstract:

Consider, as nodes for polynomial interpolation, the*n*th roots of unity. For a sufficiently smooth function $f(z)$, we require a polynomial $p(z)$ to interpolate

*f*and certain of its derivatives at each node. It is shown that the so-called PĂłlya conditions, which are necessary for unique interpolation, are in this setting also sufficient.

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## Additional Information

- © Copyright 1980 American Mathematical Society
- Journal: Trans. Amer. Math. Soc.
**259**(1980), 621-628 - MSC: Primary 30E05
- DOI: https://doi.org/10.1090/S0002-9947-1980-0567101-0
- MathSciNet review: 567101