Response to Casey's question

I found 7 by using a similar viewing mindow as you but when it looked crowded on the graph, I zoomed in. It is surprising how little you see when you are zoomed out so far. The way the calculator works is it only shows you what it can fit. This means that the farther you zoom out the more your graph is going to look like a line. It can only show you so much because the pixels are only so small.