Semidivisible number
= Semidivisible number
= Semidivisible
{synonym}
A <positive integer> $n$ lying strictly between consecutive <prime> squares $p^2<n<q^2$ that is divisible by exactly one of $p,q$. Within a fixed band, the sum is the sum of multiples of $p$ plus the sum of multiples of $q$ minus twice the sum of multiples of $pq$, an <inclusion-exclusion> calculation using <arithmetic progressions>.