This is my 3rd diagram, showing 3,4,5 circles in 1. i have found using the "Geometry Expressions Demo" that for 3 in 1 circle, the radius is ~46.4% of the large circle. the others are 4in1: Y2=41.3%, and 5in1 Y4=37%

Ignore large circle is a Radius 4 Doc, they were poor attempts at trying to convey my question.

Question restated: for x#of circles inside 1, what is the equation for x circles radii ? for example, R1(.5-(.04(x-2))) where R1 is the outer circle radius, and x is the # of circles past 2