Abstract
We establish a link between the basic properties of the discriminant of periodic second-order differential equations and an elementary analysis of Herglotz functions. Some generalizations are presented using the language of self-adjoint extensions.
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Pankrashkin, K. A remark on the discriminant of Hill’s equation and Herglotz functions. Arch. Math. 102, 155–163 (2014). https://doi.org/10.1007/s00013-014-0612-x
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DOI: https://doi.org/10.1007/s00013-014-0612-x