With the Premium subscription, you will access at low price to the whole curriculum,of computational mathematics currently developped by Mathedu.
The curriculum starts with a series of courses about numbers, from the natural integers to real numbers.
These courses prepare the field for real analysis (Calculus), which itself leads to numerical analysis (computational mathematics).
All the courses start with Python scripting as an introduction to mathematical notions. (A course reaching the bases of Python used in the math courses is included in the bundle accessible with Premium subscription.)
And last but not least, all the examples of Python scripts are downloadable.