On splitting augmentation ideals
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- by Warren Dicks PDF
- Proc. Amer. Math. Soc. 83 (1981), 221-227 Request permission
Abstract:
Let $G$ be a group, $H$ a subgroup of $G$ and $R$ an associative ring. Write $\omega (RG)$ for the augmentation ideal of the group ring $RG$, and $\omega (RH)G$ for the right ideal of $RG$ generated by $\omega (RH)$. For $G$ finitely generated over $H$ we characterize, in terms of the Bass-Serre theory of groups acting on trees, the situation where $\omega (RH)G$ is an $RG$-summand of $\omega (RG)$.References
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Additional Information
- © Copyright 1981 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 83 (1981), 221-227
- MSC: Primary 16A27
- DOI: https://doi.org/10.1090/S0002-9939-1981-0624902-4
- MathSciNet review: 624902