[math-fun] Mathematica and precision

I've written some mathematica code to do bifurcating continued fractions. The code is pretty straight-forward, but I'm not an experienced mathematica programmer, so I'm sure there are some optimisations that could be done. Something's going wrong with it now; I think it has to do with precision or some other nasty implementation issue. I get the first convergents correct, but later ones are dodgy. Does anyone feel qualified and generous enough to take a look? -- Mike Stay staym@datawest.net