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تسجيل مستخدم جديدTitchmarsh-Weyl formula for the spectral density of a class of Jacobi matrices in the critical case
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We consider a class of Jacobi matrices with unbounded entries in the so called critical (double root, Jordan box) case. We prove a formula for the spectral density of the matrix which relates its spectral density to the asymptotics of orthogonal polynomials associated with the matrix.
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