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Abstract: The Cauchy-Frobenius lemma (also known as the Polya-Burnside lemma and as "a lemma that is not Burnside's") is the classical tool for counting objects modulo a group of symmetries. This talk begins with a short introduction to the lemma. An ambitious example of a symmetry reduction is presented: a reduction of the set of Rubik's cube positions modulo the group of symmetries of a cube (m3m), which has been to useful in both theoretical analysis and computational analysis of Rubik's cube. The talk concludes with the calculation of the number of cube positions modulo the symmetry reduction.