Giovanni Lucca, Generalized Fibonacci circle chains,
Forum Geometricorum, 10 (2010) 131--133.
Abstract: We consider a particular circle chain where, each circle belonging
to it, is tangent to the two previous ones and to a common straight line.
We give a simple formula for calculating the limit point of the chain in
terms of the radii of the first two circles and of the golden ratio.
[ps file][pdf]