On a conjecture by Karlin and Szegö
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- by Deok H. Kim and Kil H. Kwon PDF
- Proc. Amer. Math. Soc. 124 (1996), 227-231 Request permission
Abstract:
In 1961, Karlin and Szegö conjectured : If $\{P_n(x)\}_{n=0}^\infty$ is an orthogonal polynomial system and $\{P_n’(x)\}_{n=1}^\infty$ is a Sturm sequence, then $\{P_n(x)\}_{n=0}^\infty$ is essentially (that is, after a linear change of variable) a classical orthogonal polynomial system of Jacobi, Laguerre, or Hermite. Here, we prove that for any orthogonal polynomial system $\{P_n(x)\}_{n=0}^\infty$, $\{P_n’(x)\}_{n=1}^\infty$ is always a Sturm sequence. Thus, in particular, the above conjecture by Karlin and Szegö is false.References
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Additional Information
- Kil H. Kwon
- Email: khkwon@jacobi.kaist.ac.kr
- Received by editor(s): August 12, 1994
- Communicated by: Hal L. Smith
- © Copyright 1996 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 124 (1996), 227-231
- MSC (1991): Primary 33C45, 42C05
- DOI: https://doi.org/10.1090/S0002-9939-96-03144-9
- MathSciNet review: 1301033