Hello MathML!

This mathematical formula with a big summation and the number pi:

\sum_{n = 1}^{+ ∞} \frac{1}{n^{2}} = \frac{π^{2}}{6}

is easy to prove. And was easy to markup. I just stole the MathML directly from the MathML Core documentation.

The fraction $\frac{1}{3}$ is not a decimal number (I got this example from Getting started with MathML and styled it using CSS).

I made this one: $\frac{\frac{1}{4}}{2 + 3}$ as a solution to the last exercise on this same page.

I'm going to need a lot of Unicode characters for this math markup, and I'll use Mathematical operators and symbols in Unicode and List of logic symbols as primary resources (thanks Wikipedia!)

P ∧ Q, P ∨ Q, P → Q, P ↔ Q, ¬P → ¬Q