Say you want to count like this in mediawiki (not starting at 1):
The internet tells you it's not possible natively and that you need an extension. Here's an ugly hack to do it anyway! (keeping the # rather than going full HTML).
<div style="color:white;"> # <ol start=3><div style="color:black; position:relative; left:-50px;"> # Three # Four # Five</div></ol></div>
It's ugly and could break your document! Use with care under desperate circumstances! Here's an example with the multicol template:
which gives me a nicely-ordered, neatly-displayed list of my Mathematics's Wolverhampton lectures of Physics. Fourier Series are covered in Lecture 17!
Here's a template of how to get this:
{{multicol}}
# item 1
# item 2
{{multicol-break}}
<div style="color:white;">
# <ol start=3><div style="color:black; position:relative; left:-50px;">
# item 3
# item 4</div></ol></div>
{{multicol-end}}