Answer
The wave will approach the shape of the square wave.
Work Step by Step
This problem involves Fourier series, so most graphing calculators will not work. Rather, it is necessary to use a Fourier series plotter or to create one by yourself (with a program such as MATLAB). What you will see is that the more points that you plot, the more the graph will resemble the square function. When you plot only 3 terms, it is only a slight resemblance, but when you plot 10 terms, the resemblance will become more noticeable. If you try 100 terms, the two shapes should look very similar.