Oscillation and nonoscillation theorems for certain second-order difference equations with forcing term

In this paper we are concerned with some new criteria for the oscillation and nonoscillation of the second-order nonhomogeneous linear difference equations of the form Delta(c(n-1)Delta x(n-1)) + q(n)x(n) = f(n), n = 1,2,..., where {c(n)}, {f(n)}, and {q(n)} are real sequences, c(n) > 0 for n greater than or equal to 0, and Delta x(n) = x(n+1) - x(n) is the forward difference operator. The discrete analogs of some of the known results in the continuous case are presented. (C) 1997 Academic Press.