Oscillation of fourth order nonlinear neutral difference equations-II

Oscillatory and asymptotic behaviour of solutions of a class of fourth order nonlinear neutral difference equations of the form Delta(2)(r(n)Delta(2()y(n) + p(n)y(n-m))) + q(n)G(y(n-k)) = 0 and (E)Delta(2)(r(n)Delta(2()y(n) + p(n)y(n-m))) + q(n)G(y(n-k)) = f(n) are studied under the assumption Sigma(n)(n=0 r(n)) < infinity, for different ranges of p(n). Sufficient conditions are obtained for the existence of positive bounded solutions of (E). (c) 2008 Mathematical Institute Slovak Academy of Sciences.