Canonical forms for boundary conditions of self-adjoint odd-order differential operators

Abstract

It is useful to have canonical forms of boundary conditions in the study of the eigenvalues of boundary value problems and associated numerical applications. In [J. Appl. Anal. Comput., 2024, 14(4), {1854--1868}], a canonical form is given for self-adjoint differential operators of even order, with eigenvalue parameter dependent boundary conditions. In this article, we derive canonical forms for the remaining case, namely: for self-adjoint $(2n+1)$-th order differential operators with eigenvalue parameter dependent boundary conditions.