  For a prime $p>3$ and $a\in \Bbb Z$ with $p\nmid a$ let $V_p(x^2+\frac ax)$
be the residue-counts of $x^2+\frac ax$ modulo $p$ as $x$ runs over
$1,2,\ldots,p-1$. In this paper, we obtain an explicit formula for
$V_p(x^2+\frac ax)$, which is concerned with cubic residues and binary
quadratic forms.
