A charge +q is placed at each of the points x=x_0, x=3 x_0, x=5...

A charge $+q$ is placed at each of the points $x=x_0, x=3 x_0, x=5 x_0, x=7 x_0 \ldots \ldots \ldots \ldots . . \infty$ on the $x$-axis and a charge $-q$ is placed at each of the points $x=2 x_0, x=4 x_0, x=6 x_0, x=8 x_0 \ldots \ldots \infty$ here $x_0$ is a positive constant. Take the electric potential at a point due to a charge $q$ at a distance $r$ from it to be $\mathrm{V}=\frac{1}{4 \pi \varepsilon_0} \frac{q}{r}$. The electric potential at the origin due to the above system of charges is