Subgroups of 3-Factor Direct Products

@article{Neuen2019SubgroupsO3,
  title={Subgroups of 3-Factor Direct Products},
  author={Daniel Neuen and Pascal Schweitzer},
  journal={Tatra Mountains Mathematical Publications},
  year={2019},
  volume={73},
  pages={19 - 38}
}
Abstract Extending Goursat’s Lemma we investigate the structure of subdirect products of 3-factor direct products. We construct several examples and then provide a structure theorem showing that every such group is essentially obtained by a combination of the examples. The central observation in this structure theorem is that the dependencies among the group elements in the subdirect product that involve all three factors are of Abelian nature. In the spirit of Goursat’s Lemma, for two special… Expand
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