Superlinear higher order boundary value problems (Q1296957)

For a higher-order nonlinear ordinary differential equation the authors consider two boundary value problems with boundary conditions stipulating that some of the derivatives vanish at the ends of the interval. The existence of nonnegative solutions is studied for the \((k,n-k)\) conjugate boundary value problem and the focal boundary value problem. The considerations are based on a nonlinear alternative of Leray-Schauder type.