 Agranovich–Dynin formula

The Agranovich–Dynin formula is a mathematical result in the field of partial differential equations, particularly in the study of the spectral properties of self-adjoint operators. It provides a way to relate the spectral analysis of certain operators to the behavior of solutions of the differential equations associated with those operators. The formula is particularly relevant in the context of boundary value problems, where it can be used to analyze the distribution of eigenvalues and the properties of the eigenfunctions of the associated differential operators.