A cyclic permutation of length n is a permutation that shifts each element one position to the right (or left) in a cycle. For example, the cyclic permutation (1 2 3 4 5) maps 1 to 2, 2 to 3, 3 to 4, 4 to 5, and 5 to 1.
The order of a cyclic permutation of length n is n, because it takes n applications of the permutation to return to the original arrangement.
The set of integers, denoted by Z, forms an abelian group under the operation of addition (+). This means that the following properties hold:
Closure: For any integers a, b, their sum a + b is also an integer.
Associativity: (a + b) + c = a + (b + c) for any integers a, b, c.
Commutativity: a + b = b + a for any integers a, b.
Identity: There exists an identity element, which is 0, such that a + 0 = a for any integer a.
Inverse: For each integer a, there exists an inverse element, which is -a, such that a + (-a) = 0.
The set of integers does not form a group under multiplication, because the inverse property does not hold (except for 1 and -1). Division is not even a binary operation on the set of integers, because it is not defined for all pairs of integers (e.g., 1/2 is not an integer).
In a group (G, *), the binary operation * is defined in such a way that the result of combining any two elements is always an element in the group. Therefore, if a, b ∈ G, then a * b ∈ G.