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MiS Preprint
45/1999
Nontrivial extreme networks. Singularities of Lagrange functions and criterion of extremality
Alexandr O. Ivanov, Hông Vân Lê and Alexey A. Tuzhilin
Abstract
In this note we consider the following problem
what Lagrangians' properties lead to the existence of nontrivial branching extremals,
what is the local structure of the branching extremals.
It turns out that the existence of nontrivial extreme networks is related closely with the presence of singularities of Lagrangian. For an wide class of Lagrangian we obtain a criterion of networks' extremality.