Asymptotic behaviour of the positive spectrum for a family of periodic Sturm-Liouville problems in the transition from a definite problem to indefinite one

D. A. Popov

Spectral problem for a family of periodic Sturm--Liouville problems \[ u''+λ^2(a(x)-a)u=0 \] depending on the parameter (a\in\mathbb R) is considered. An interpolation formula desc…