A quasi-orthogonal cocycle, defined over a group of order congruent to 2 modulo 4, is naturally analogous to an orthogonal cocycle (i.e., one defined over a group of order divisible by 4, and whose display matrix is Hadamard). Here we extend the theory of quasi-orthogonal cocycles in new directions, using equivalences with various optimal binary and quaternary sequences.

中文翻译：

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拟正交循环，最优序列和Littlewood猜想

在与2模4相等的一组阶上定义的准正交共轭环自然地类似于正交的Cocycle（即，在被4整除的一组阶上定义的准正交环，其显示矩阵为Hadamard）。在这里，我们使用具有各种最佳二元和四元序列的等价关系，在新方向上扩展了准正交星轮理论。