$$16x^{4}-4x^{2}-4x-1$$
$16x^{4}-\left(2x+1\right)^{2}$
$4\left(x-\frac{1-\sqrt{5}}{4}\right)\left(x-\frac{\sqrt{5}+1}{4}\right)\left(4x^{2}+2x+1\right)$
