List number fixed, but with indented paragraphs

[Tom McTavish]

I'm trying to make a style for writing pseudocode. I want the
pseudocode to be numbered so that in my discussion of it, I can
reference individual line numbers. This is how I want it to look:

1. First, normal line
2. Second may be indented, but number stays to the left.
3. Third line even further indented, but number stays left
4. Another line like so
5. And the last line

The problem is that when I indent, I get normal outline results:

1. First, normal line
a. Second may be indented, but number stays to the left.
ii. Third line even further indented, but number stays left
2. Another line like so
3. And the last line

This second example is NOT what I want. I want the first example that
maintains the numbering of the first level, but allows me to indent
the paragraphs of other levels.

Thanks,
Tom