Sufficient conditions for the eigenvalues of the operator \(-d^2/dx^2+q(x)\) under the Ionkin-Samarskii conditions
The authors propose and substantiate an exponentially converging functional-discrete (FD) method for the Sturm-Liouville problem under the Ionkin-Samarskii conditions. Until recently, sufficiently general restrictions under which all the eigenvalues are real have not been found. Using the method under consideration, this problem is solved. The results of numerical experiments are presented.
scientific article; zbMATH DE number 1779341