On the basis property of the root function systems of regular boundary value problems for the Sturm-Liouville operator

Abstract

We consider the nonselfadjoint Sturm-Liouville operator Lu=u''-q(x)u with regular but not strongly regular boundary conditions, where q(x)is an arbitrary complex-valued summable function. We examine the basis property for the root function system of the mentioned operator.

Submitted to Differ. Uravn