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arXiv · 2103.15161

Commutator Equations in Finite Groups

Kanto Irimoto·Enrique Torres-Giese
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Abstract

The problem of finding the number of ordered commuting tuples of elements in a finite group is equivalent to finding the size of the solution set of the system of equations determined by the commutator relations that impose commutativity among any pair of elements from an ordered tuple. We consider this type of systems for the case of ordered triples and express the size of the solution set in terms of the irreducible characters of the group. The obtained formulas are natural extensions of Frobenius' character formula that calculates the number of ways a group element is a commutator of an ordered pair of elements in a finite group. We discuss how our formulas can be used to study the probability distributions afforded by these systems of equations, and we show explicit calculations for dihedral groups.

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Kanto Irimoto, Enrique Torres-Giese. 2021-03-28. Commutator Equations in Finite Groups. https://doi.org/10.1017/s0017089521000124

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