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  • In abstract algebra, a generating set of a group is a subset such that every element of the group can be expressed as the combination of finitely many elements of the subset and their inverses. In other words, if S is a subset of a group G, then <S>, the subgroup generated by S, is the smallest subgroup of G containing every element of S, meaning the intersection over all subgroups containing the elements of S; equivalently, <S> is the subgroup of all elements of G that can be expressed as the finite product of elements in S and their inverses. If G = <S>, then we say S generates G; and the elements in S are called generators or group generators. If S is the empty set, then <S> is the trivial group {e}, since we consider the empty product to be the identity. When there is only a single element x in S, <S> is usually written as <x>. In this case, <x> is the cyclic subgroup of the powers of x, a cyclic group, and we say this group is generated by x. Equivalent to saying an element x generates a group is saying that <x> equals the entire group G. For finite groups, it is also equivalent to saying that x has order |G|.

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