Definition:Quasiamicable Numbers/Definition 1

Definition
Let $m \in \Z_{>0}$ and $n \in \Z_{>0}$ be (strictly) positive integers. $m$ and $n$ are quasiamicable numbers :
 * the sum of the proper divisors of $m$ is equal to $n$

and:
 * the sum of the proper divisors of $n$ is equal to $m$.

Also see

 * Equivalence of Definitions of Quasiamicable Numbers