i know your allowed 3 o he same page but dont really know about the distance but i assume you can place there where ever
Yes you can place them any where on the site. There are other restrictions to keep in mind though. Read more at https://www.google.com/adsense/supp...=aso&subid=ww-ww-et-asui&medium=link&hl=en_US and scroll down to Ad Placement.
You can do what you are suggesting, but keep in mind that some visitors may think that a bunch of ads piled into one portion of the site makes it look "cheap" Also, depending upon how much other content you have, it may give the impression that there is more ads than content since they are all stacked together rather than spread out, thus they will stand out more and possibly dominate the look of the page.