Functions with low differential uniformity have relevant applications in cryptography. Recently, functions with low c-differential uniformity attracted lots of attention. In particular, so-called APcN and PcN functions (generalization of APN and PN functions) have been investigated. Here, we provide a characterization of such functions via quadratic polynomials as well as non-existence results.

中文翻译：

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关于c-（几乎）理想非线性函数的构造和（不存在）。

差分均匀性低的功能在密码学中具有相关的应用。近来，具有低c-差分均匀性的功能引起了很多关注。特别地，已经研究了所谓的APcN和PcN功能（APN和PN功能的概括）。在这里，我们通过二次多项式以及不存在的结果来表征此类函数。