Convexity of the zeros of some orthogonal polynomials and related functions

نویسندگان

  • Kerstin Jordaan
  • Ferenc Toókos
چکیده

We study convexity properties of the zeros of some special functions that follow from the convexity theorem of Sturm. We prove results on the intervals of convexity for the zeros of Laguerre, Jacobi and ultraspherical polynomials, as well as functions related to them, using transformations under which the zeros remain unchanged. We give upper as well as lower bounds for the distance between consecutive zeros in several cases. AMS MOS Classification: 33C45, 34C10, 42C05

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عنوان ژورنال:
  • J. Computational Applied Mathematics

دوره 233  شماره 

صفحات  -

تاریخ انتشار 2009