DOI

Our goal is to find an asymptotic behavior as n→∞ of orthogonal polynomials P n(z) defined by the Jacobi recurrence coefficients a n,b n. We suppose that the off-diagonal coefficients a n grow so rapidly that the series ∑a n −1 converges, that is, the Carleman condition is violated. With respect to diagonal coefficients b n we assume that −b n(a na n−1) −1/2→2β for some β ≠±1. The asymptotic formulas obtained for P n(z) are quite different from the case ∑a n −1=∞ when the Carleman condition is satisfied. In particular, if ∑a n −1<∞, then the phase factors in these formulas do not depend on the spectral parameter z∈C. The asymptotic formulas obtained in the cases |β |<1 and |β |>1 are also qualitatively different from each other. As an application of these results, we find necessary and sufficient conditions for the essential self-adjointness of the corresponding minimal Jacobi operator.

Язык оригиналаанглийский
Номер статьи108648
Число страниц37
ЖурналJournal of Functional Analysis
Том279
Номер выпуска7
Дата раннего онлайн-доступа20 мая 2020
DOI
СостояниеОпубликовано - 15 окт 2020

    Предметные области Scopus

  • Анализ

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