Hey, I'm just starting out in Pd and I'm confused on how I would replicate a mathematical function. What I'm trying to do is generate a harmonic tree which is defined by the function...

x = value
d = destination harmonic
r = relative harmonic

f(xn+1) = f(xn) * d / r

The description of the site is here http://www.csounds.com/ezine/trees/

So what I have kind of does that but my question is, Can i create a patch that will do this can call itself again? (The f(xn) within the f(xn+1) part kind of confuses me)

Here is what I have so far..

Thanks.