"Makes sense to me."<p>Me too.<p>But: when I see code that refers to first and last, I expect that the first and last elements are special.<p>When I see integers, it leads me to think that all of the elements are about equally important.<p>I also find it easier to read the text form rather than the integers; I don't have to look carefully to see if it's 1, 11, 7; code reading goes more smoothly.<p>Having both forms allows me to express, and parse, intention better.