Here I tried 3 things:
- Sin control of circle radius as explained in the course (image 1)
- Replacement of one circle radius with List commands (image 2)
- Make a control curve to change the profile of the stacked circles (image 3).
image 1: sin function applied to circles.
image 2: replace one radius value with List commands.
image 3: read the X values of a subdivided curve to set the profile radius of the circles.