I have a need to number all paragraphs (as in body text) with numbers which include the Heading level. I cannot use a Heading level for this (as the text may be at different levels. And I cannot find a way of prefixing a ListNum with the heading level. What I am trying to achieve looks something like this:

1. First Heading level 1
1.1 Heading level 2
1.1.1 Lots of body text
1.1.2 Lots of body text
1.2 Another Heading Level 2
1.2.1 Heading Level 3
1.2.1.1 Lots of body text
1.2.1.2 Lots of body text
1.3 Another Heading Level
1.3.1 Lots of body text
etc
So the body text is at different levels. Is there a way of doing this without manual numbering?