Google Colab headers don't show prepended number in Table of Contents

Question

In Google Colaboratory, I like to create markdown section headers with a prepended number, like so:

# 1. My Notebook

-----

## 1. My section

However, when I look at the Table of Contents pane, the number does not show up.

When I instead use a letter, such as "A", the letter does show up.

How do I fix it so that the prepended numerals (e.g. 1.) show up in the Table of Contents?

Answer 1

You can write it like this:

# 1. Heading
## 1.1 Sub-Heading

Using   to replace the space.