摘要:We present some interesting facts connected with the following second-order difference equation: x n + 2 − q n x n = f n , n ∈ N 0 , $$x_{n+2}-q_{n}x_{n}=f_{n},\quad n\in \mathbb{N}_(, $$ where ( q n ) n ∈ N 0 $(q_{n})_{n\in\mathbb{N}_(}$ and ( f n ) n ∈ N 0 $(f_{n})_{n\in\mathbb {N}_(}$ are given sequences of numbers. We give some sufficient conditions for the existence of a unique bounded solution to the difference equation and present an elegant proof based on a combination of theory of linear difference equations and the Banach fixed point theorem. We also deal with the equation by using theory of solvability of difference equations. A global convergence result of solutions to a linear first-order difference equation is given. Some comments on an abstract version of the linear first-order difference equation are also given.
关键词:second-order difference equation ; unique bounded solutions ; fixed point theorem ; linear first-order difference equation