An infinite number of point charges each with magnitude q are placed at x=1,x=2,x=4,x=8 and so on?

Presumably, the charges would roughly cancel each other out, so the only one of any importance is the first one, so Q.
Alternatively, infinite, depending on how fatuous you are.

But then, I'm only taking college-level physics, and this sounds pretty advanced, so don't take my word for it.