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divides

Symbol $\mid$ -- $b \mid a$ means $a=bk$ for some integer $k$ .

For integers $a, b$ , $b$ divides $a$ (written $b\mid a$ ) if there exists an integer $k$ with $a=bk$ .

Examples

$3 \mid 12$ is true, since $12=3(4)$ .
$5 \mid 12$ is false -- no integer k makes 12=5k.