Generating Random Elements in Finite Groups
نویسنده
چکیده
Let G be a finite group of order g. A probability distribution Z on G is called ε-uniform if |Z(x) − 1/g| ≤ ε/g for each x ∈ G. If x1, x2, . . . , xm is a list of elements of G, then the random cube Zm := Cube(x1, . . . , xm) is the probability distribution where Zm(y) is proportional to the number of ways in which y can be written as a product x1 1 x ε2 2 · · · xεm m with each εi = 0 or 1. Let x1, . . . , xd be a list of generators for G and consider a sequence of cubes Wk := Cube(x −1 k , . . . , x −1 1 , x1, . . . , xk) where, for k > d, xk is chosen at random from Wk−1. Then we prove that for each δ > 0 there is a constant Kδ > 0 independent of G such that, with probability at least 1−δ, the distribution Wm is 1/4-uniform when m ≥ d + Kδ lg |G|. This justifies a proposed algorithm of Gene Cooperman for constructing random generators for groups. We also consider modifications of this algorithm which may be more suitable in practice.
منابع مشابه
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 15 شماره
صفحات -
تاریخ انتشار 2008