The Seidel, Stern, Stolz and Van Vleck Theorems on continued fractions

We unify and extend three classical theorems in continued fraction theory, namely the Stern–Stolz Theorem, the Seidel–Stern Theorem and Van Vleck’s Theorem. Our arguments use the group of Mobius transformations both as a topological group and as the group of conformal isometries of three-dimensional hyperbolic space.