Co-small Module

Wang Li, Cuncheng Jin


The main goal of the present article is to study basic properties of co-small modules. Let $R$ be a Noetherian ring, For all co-small module $B$ and index $I$, we get isomorphic $Torn(B;\prod A_i)\cong \prod Torn(B;A_i)$. Finally, we prove that If two modules of the sequence $0 \to A\to B\to C\to 0$ are co-small modules, so is the third.


Co-small modules; Strong modules; Semisimple and noetherian ring

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