English

Para-orthogonal polynomials on the unit circle generated by Kronecker polynomials

Classical Analysis and ODEs 2021-07-27 v1

Abstract

The Kronecker polynomial K(z)K(z) is a finite product of cyclotomic polynomials Cj(z)C_j(z). Any Kronecker polynomial K(z)K(z) of degree N+1N+1 with simple roots on the unit circle generates a finite set Φ0=1,Φ1(z),,ΦN(z)\Phi_0=1, \Phi_1(z), \dots, \Phi_N(z) of polynomials (para) orthogonal on the unit circle (POPUC). This set is determined uniquely by the condition ΦN(z)=(N+1)1K(z)\Phi_N(z) = (N+1)^{-1} K'(z). Such set can be called the set of Sturmian Kronecker POPUC. We present several new explicit examples of such POPUC. In particular, we define and analyze properties of the Sturmian cyclotomic POPUC generated by the cyclotomic polynomials CM(z)C_M(z). Expressions of these polynomials strongly depend on the decomposition of MM into prime factors.

Keywords

Cite

@article{arxiv.2107.11430,
  title  = {Para-orthogonal polynomials on the unit circle generated by Kronecker polynomials},
  author = {Alexei Zhedanov},
  journal= {arXiv preprint arXiv:2107.11430},
  year   = {2021}
}

Comments

12 pages, 15 references

R2 v1 2026-06-24T04:28:32.437Z