[Profpat]

Thank you;

I thought maybe it was the one for a circle which is an exponential equation of course, but I had no idea as to how to combine a formula for 3 circles intertwined.

I think both you and AntonioLao are the two best mathematicians on the block.

We ( the 3 of us ) can even do a paper on the Idea, if you think it's worth the effort.

Best to all,

Pat