So, as per this related post , I've tried to use the <math> tags to show a summation. This is what I'v done:

<html><math>

∑<sub>k=0</sub><sup>k=10</sup> i<sub>k</sub>

</math></html>

It does not work. This is what I get:

As per this link, the <math> tag is a valid one.

https://www.w3.org/MarkUp/HTMLPlus/htmlplus_45.html

Any other ideas on how to use pretty math formulae in labels, either node or edge labels? Latex would be a big plus ... :-) ... !

Thanks!