Fund Project:Supported by the NNSFC(10071022), Mathematical Tianyuan Foundation ofChina (Ty10026002-01-05-03), and Shanghai Priority Academic Discipline.
A new sufficient condition is given for the global attractivity of solutions of the delay difference equation xn+1=xnf(xn,xn-1), n = 0,1…,As an application, our results partly confirm a conjecture of G. Ladas.