Elliptic Solutions of Dynamical Lucas Sequences

Entropy (Basel). 2021 Jan 31;23(2):183. doi: 10.3390/e23020183.

Abstract

We study two types of dynamical extensions of Lucas sequences and give elliptic solutions for them. The first type concerns a level-dependent (or discrete time-dependent) version involving commuting variables. We show that a nice solution for this system is given by elliptic numbers. The second type involves a non-commutative version of Lucas sequences which defines the non-commutative (or abstract) Fibonacci polynomials introduced by Johann Cigler. If the non-commuting variables are specialized to be elliptic-commuting variables the abstract Fibonacci polynomials become non-commutative elliptic Fibonacci polynomials. Some properties we derive for these include their explicit expansion in terms of normalized monomials and a non-commutative elliptic Euler-Cassini identity.

Keywords: Lucas sequences; elliptic numbers; non-commutative Fibonacci polynomials; theta functions.