The problem of convergence of branched continued fractions
https://doi.org/10.15330/cmp.18.2.447-464
Keywords:
branched continued fraction, convergence, approximant, figured convergenceAbstract
Using the tails of the approximants of continued fractions and their multidimensional generalizations, branched continued fractions, canonical numerators and denominators have been defined, and the conditions for the degeneracy of approximants have been investigated. Certain types of figured approximants, specifically $\mathcal{A}$-, $\mathcal{B}$-, and $\mathcal{C}$-figured approximants and their applications, are considered. Various types of convergence for continued and branched continued fractions have been classified. By analogy with Leighton's example, a $\mathcal{C}$-figured-convergent two-dimensional branched continued fraction with independent variables has been constructed; in its structure, every fourth element in each constituent continued fraction is an arbitrary complex number different from $0$ and $-1/2$. Methods for investigating the convergence of branched continued fractions are analyzed.