A circle of circles

[Sariaht]

A circle with the radius R cuts the centers of circles with the radius r that does mearly touch eachother, What is the equation for the number of circles in the circle?

[Gokul43201]

No.~of~circles,~n=[\frac{\pi}{sin^{-1}(r/R)}]

where [ ] represents the greatest integer (or floor) function.

[kishtik]

Can you give a proof please?

[kishtik]

You cant? :rofl: And im too lazy to look it up at the library...