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Results tagged with gr.group-theory
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user 25869
Questions about the branch of algebra that deals with groups.
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Non-split extension of the rationals by the integers
Can someone describe explicitly an abelian group $A$ such that the extension $$0 \to \mathbb{Z} \to A \to \mathbb{Q} \to 0$$ doesn't split ?
Background: The Stein-Serre theorem (Hilton, Stammbach: A …
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