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arXiv · 2010.09178

Hamiltonian Groups with Perfect Order Classes

James McCarron
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Abstract

A finite group is said to have "perfect order classes" if the number of elements of any given order is either zero or a divisor of the order of the group. The purpose of this note is to describe explicitly the finite Hamiltonian groups with perfect order classes. We show that a finite Hamiltonian group has perfect order classes if, and only if, it is isomorphic to the direct product of the quaternion group of order $8$, a non-trivial cyclic $3$-group and a group of order at most $2$. Theorem. A finite Hamiltonian group has perfect order classes if, and only if, it is isomorphic either to $Q\times C_{3^k}$ or to $Q\times C_{2}\times C_{3^k}$, for some positive integer $k$.

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James McCarron. 2021-05-05. Hamiltonian Groups with Perfect Order Classes. https://doi.org/10.3318/pria.2021.121.01

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