While sitting in a coffee shop last week, an estranged economist asked me what the sum of the first n square numbers is. If you already know the formula, proving it is an easy exercise with induction. But how do you create the formula? Below is a Prezi presentation on my favorite derivation of the sum of the first squares.

The point of the presentation is not to show you the construction, though I do enjoy it, but to introduce an alternative to beamer (or power point). Prezi is a web based presentation editor; for the most part it is a virtual poster that you can navigate around. I am new to Prezi so I have not had time to play around, but here is what I think so far.

**Pros: **

- Very easy to use and learn
- Web based
- Free upgrade with edu email address [http://prezi.com/profile/signup/edu/]
- A fresh look that lets you really personalize your talk. I think most beamer talks feel the same; it is difficult to really express yourself with beamer. Personally, I enjoy talks more when I am not just reading facts on a screen.
- Very easy to add a school logo to the presentation. You cannot see it in the embedded version though. But when you download the talk to present, you have the option of attaching a personal logo.
- Dynamic; in the sense that you are not tied to a particular slide order. You are free to navigate the Prezi canvas. This feature might be nice if you are asked a question during your talk.
- Easy to embed pictures and video.

**Cons: **

- No LaTeX support. This is a very big con. You have to be clever if you want to use LaTeX in your Prezi talk. In my presentation below, all squares and the main formula are products of LaTeX, the rest is Prezi. In reading about this issue, I came across a nice Blog post [A Math Prezi].
- Can make audience dizzy if used poorly
- As with beamer, you can spend many hours working on how your presentation looks.
- No LaTeX support. Did I mention this already?
- No spell check in the editor

There is more to say, but you can read the Prezi web site if you are interested. I hope you enjoy my presentation (it’s short).