Involving the notion of strongly Schur-convex functions we give a new characterization of inner product spaces among norm spaces. We also present a representation theorem for functions which generate strongly Schur-convex sums.

中文翻译：

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用强 Schur-Convex 函数表征内积空间

涉及强 Schur-凸函数的概念，我们给出了范数空间中内积空间的新特征。我们还提出了生成强 Schur-凸和的函数的表示定理。