without latex delimiters the `_{i=1}` in `\sum_{i=1}^n a_n` is interpreted as subscript. we support `\(...\)`, `\[...\]`, `$$...$$` and `\begin{$env}...\end{$env}` as latex fragment delimiters.

- ∑i=1^n a_n (without latex delimiter)

- \(\sum_{i=1}^n a_n\)

- \[\sum_{i=1}^n a_n\]

- $$\sum_{i=1}^n a_n$$

- \begin{xyz}\sum_{i=1}^n a_n\end{xyz}

- \begin{xyz} \sum_{i=1}^n a_n \end{xyz}

- $2 + 2$, $3 - 3$