Gritsans, A.; Sadyrbaev, F. Unexpected solutions of the Nehari problem. (English) Zbl 1390.34058 Int. J. Anal. 2014, Article ID 467831, 5 p. (2014). Summary: The Nehari characteristic numbers \(\lambda_n (a,b)\) are the minimal values of an integral functional associated with a boundary value problem (BVP) for nonlinear ordinary differential equation. In case of multiple solutions of the BVP, the problem of identifying of minimizers arises. It was observed earlier that for nonoscillatory (positive) solutions of BVP those with asymmetric shape can provide the minimal value to a functional. At the same time, an even solution with regular shape is not a minimizer. We show by constructing the example that the same phenomenon can be observed in the Nehari problem for the fifth characteristic number \(\lambda_n (a,b)\) which is associated with oscillatory solutions of BVP (namely, with those having exactly four zeros in \((a,b)\). MSC: 34B15 Nonlinear boundary value problems for ordinary differential equations Keywords:Nehari problem; Nehari characteristic numbers; nonlinear boundary value problem; asymmetric solutions PDFBibTeX XMLCite \textit{A. Gritsans} and \textit{F. Sadyrbaev}, Int. J. Anal. 2014, Article ID 467831, 5 p. (2014; Zbl 1390.34058) Full Text: DOI