Honam Mathematical Journal (호남수학학술지)

The Honam Mathematical Society (호남수학회)
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A GENERALIZATION OF THE SCHUR-COHN TEST

  • Lee, You-Ho (Department of Internet Information, Daegu Haany University)
  • Received : 2007.11.08
  • Published : 2007.12.25
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Abstract

In this note we provide a generalization of the Schur-Cohn test. If $p_n$ be a polynomial of degree n then $p_n$ is a reduced-stable polynomial whose reduced degree is equal to r if and only if $D_n\;:=\;P_nQ_n^{-1}$ is a contraction such that rank ($I-D_nD_n^*$) = r.

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References

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