Definition:Cofinite
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Definition
Let $S$ be a set, and let $A$ be a subset of $S$.
$A$ is cofinite in $S$ if the complement of $A$ in $S$ is finite.
Let $S$ be a set, and let $A$ be a subset of $S$.
$A$ is cofinite in $S$ if the complement of $A$ in $S$ is finite.