Multiplication of permutations, unlike multiplication of numbers, is not always commutative . 置换的乘法不同于数的乘法,它并不一定满足交换律。
This classification is called the parity of the permutation analogous to the definition of parity of integers . 这种分类叫作置换的奇偶性,类似于整数偶性的定义。
It turns out that all these problems can be solved at once, provided we learn enough about the cycle structure of permutations . 结果是,所有这些问题都可以一次解决,只要我们充分地了解各置换的循环结构。
On the parity of arrangements and permutations 关于排列与置换的奇偶性
On the construction of orthomorphic permutations 关于正形置换的构造