Nonlinear complexity, as an important measure for assessing the randomness of sequences, is defined as the length of the shortest feedback shift registers that can generate a given sequence. In this paper, the structure of n-periodic binary sequences with nonlinear complexity larger than or equal to 3n/4 is characterized. Based on their structure, an exact enumeration formula for the number of such periodic sequences is determined.

翻译：非线性复杂度作为评估序列随机性的重要度量，其定义为能够生成给定序列的最短反馈移位寄存器的长度。本文刻画了非线性复杂度大于等于3n/4的n周期二进制序列的结构特征。基于该结构特征，我们推导出了此类周期序列数量的精确枚举公式。