Forum now runs discourse-math plugin which allows LaTeX-like math.

Simple inline math like \sqrt{n+1} can be written in with `$\sqrt{n+1}$`

Display-mode math can be written like follows (**Note:** dollar-signs must on their own lines):

```
$$
\sum^{\infty}_{n=1} \frac{1}{n}
$$
```

Which will show up as

\sum^{\infty}_{n=1} \frac{1}{n}

Please give it a shot if you write equations with more than few terms, and especially if there are combinations of fractions and whatnot.