  The height of a polynomial $f(x)$ is the largest coefficient of $f(x)$ in
absolute value. Let B(n) be the largest height of a polynomial in
$\mathbb{Z}[x]$ dividing $x^n-1$. In this paper we investigate the maximal
height of divisors of $x^{pq^b}-1$ and prove that some conjectures on the
maximal height of divisors of $x^{pq^b}-1$ are true.
