In this chapter some criteria for the oscillation of high order functional diﬀerence equation of the form ∆2(r(n)[∆(m−2)y (n)]α)+ q (n)f [y (g (n))] = 0,
∞ ∑s =n0
r− 1 α (s) < ∞ and m > 1 is discussed. Examples are given to illustrate the results.
Department of Mathematics, Nallamuthu Gounder Mahalingam College, Bharathiar University, Coimbatore, Tamil Nadu, India.
Department of Science and Humanities, Nehru Institute of Engineering and Technology, T. M. Palayam, Coimbatore, Tamil Nadu, India.