“…In function theory, the so-called Jacobi-Perron algorithm and its variations are algorithms to expand a vector of power series in a continued fraction, where the partial numerators and denominators are vectors of polynomials. Algebraic and analytic aspects of vector continued fractions have been investigated in numerous works, such as [1,2,4,6,7,8,9,13,14,19,20,23,24,25,26]. Particularly important for us are the works of Kalyagin [13,14], in which he investigated spectral properties of banded Hessenberg operators, the problem of Hermite-Padé approximation to a vector of resolvent functions of the operator, and obtained the vector continued fraction for the vector of resolvent functions.…”