This is a great question. What I really tried to emphasize in the article is that math is not a formal language. Since its just you and coworkers, write out the parts you need as you need them, and ignore details. After all, its an exercise to help you think.

If I needed uppercase I would just say:

  `up(s)` is a function that maps a string s to its uppercase string

Writing that down, you and I already have a pretty good idea of how it works, or its included in our libraries, and we can figure out the details when writing the code.

This is of course assuming `uppercase` is a minor part of another algorithm. If it was the subject of discussion I might describe it like this:

  Let `u(c)` be a function that maps a characters to its uppercase character. In ASCII `u(c) = c + K` where K is some offset.

  To capitalize an entire string we need to apply that function to each character.

  Let `up(s)` = (u(c_1), u(c_2), ... u(c_n))
  where the string s = (c_1, c_2, ... c_n)

Perhaps that helps, but I don't think it addresses your question directly. I think you need some experience reading math to know how to describe problems, but I don't think you need to know fancy math. A knowledge of functions, sets, tuples, logic, summations, etc, will get most of what you need.

I highly recommend that book I linked in the article: "Introduction to Graph Theory" By: Trudeau