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arXiv · math/0601414

The distinguishing number of the direct product and wreath product action

Melody Chan
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Abstract

Let G be a group acting faithfully on a set X. The distinguishing number of the action of G on X is the smallest number of colors such that there exists a coloring of X where no nontrivial group element induces a color-preserving permutation of X. In this paper, we consider the distinguishing number of two important product actions, the wreath product and the direct product. Given groups G and H acting on sets X and Y respectively, we characterize the distinguishing number of the wreath product of G and H in terms of the number of distinguishing colorings of X with respect to G and the distinguishing number of the action of H on Y. We also prove a recursive formula for the distinguishing number of the action of the Cartesian product of two symmetric groups S_m x S_n on [m] x [n].

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Melody Chan. 2006-01-17. The distinguishing number of the direct product and wreath product action. https://arxiv.org/abs/math/0601414

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