Quick jQuery snippet to select first x number of elements. You can also use the jQuery .slice() function which can chop up element groups into a range for you with a combination of .get();
//get first 20 anchor tags $("a").slice(0,20)
Also you can use lt pseudo selector: This matches the elements before the nth one (the nth element excluded). Numbering starts from 0.
//instead of this:
for (i=0; i