## Polynomial approximation with varying weights on compact sets of the complex plane

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- by Igor E. Pritsker PDF
- Proc. Amer. Math. Soc.
**126**(1998), 3283-3292 Request permission

## Abstract:

For a compact set $E$ with connected complement, let $A(E)$ be the uniform algebra of functions continuous on $E$ and analytic interior to $E.$ We describe $A(E,W),$ the set of uniform limits on $E$ of sequences of the weighted polynomials $\{W^n(z)P_n(z)\}_{n=0}^{\infty },$ as $n \to \infty ,$ where $W \in A(E)$ is a nonvanishing weight on $E.$ If $E$ has empty interior, then $A(E,W)$ is completely characterized by a zero set $Z_W \subset E.$ However, if $E$ is a closure of Jordan domain, the description of $A(E,W)$ also involves an inner function. In both cases, we exhibit the role of the support of a certain extremal measure, which is the solution of a weighted logarithmic energy problem, played in the descriptions of $A(E,W).$## References

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## Additional Information

**Igor E. Pritsker**- Affiliation: Institute for Computational Mathematics, Department of Mathematics and Computer Science, Kent State University, Kent, Ohio 44242-0001
- Address at time of publication: Department of Mathematics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7058
- MR Author ID: 319712
- Email: pritsker@mcs.kent.edu, iep@po.cwru.edu
- Received by editor(s): September 4, 1996
- Received by editor(s) in revised form: March 25, 1997
- Communicated by: Theodore W. Gamelin
- © Copyright 1998 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**126**(1998), 3283-3292 - MSC (1991): Primary 30E10; Secondary 30B60, 31A15, 41A30
- DOI: https://doi.org/10.1090/S0002-9939-98-04402-5
- MathSciNet review: 1452821