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A limit-point criterion for 2n-th order symmetric differential expressions

Published online by Cambridge University Press:  14 November 2011

Bernd Schultze
Affiliation:
Universität Essen, Fachbereich 6, Mathematik, 43 Essen 1, Germany

Synopsis

A perturbation theorem for symmetric differential expressions is given and applied to even-order expressions. We assume the coefficients p0(t), pn(t) to be eventually positive and to have real powers of t as dominating terms. Then we are able to admit for the absolute values of the other coefficients a rate of growth depending on the growth of both of the coefficients p0, pn in order to obtain minimal deficiency indices.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1981

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