Copy of the sum of the first n odd

Move slider [math]n[/math] to create the sum of the first [math]n[/math] odd numbers.[br]Try to predict the formula for the sum of the first [math]n[/math] odd numbers.[br]Drag the Move slider to see a dynamic proof of the formula.
Based on Alex Chik's applet: [url ]http://www.geogebratube.org/student/m18791[/url]

Information: Copy of the sum of the first n odd