Criteria of strong nearest-cross points and strong best approximation pairs

Wenxi Pan, Jingshi Xu


The concept of strong nearest-cross point (strong n.c. point) is introduced, which is the generalization of strong uniqueness of best approximation from a single point. The relation connecting to localization is discussed. Some criteria of strong n.c. points are given. The strong best approximation pairs are also studied.


Strong nearest-cross point; Local strong nearest-cross point; Strong best approximation pair

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