Abstract. General criteria of discreteness of the spectrum for operators associated to positive and unbounded Jacobi matrices are established. These criteria unify well-known previous results on compactness of the resolvent of the above matrices.
AMS Subject Classification
(1991): 47A55, 47A75
Keyword(s):
Spectral theory,
compact resolvent,
Jacobi matrices
Received November 25, 2006, and in revised from March 14, 2007. (Registered under 6455/2009.)
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