New approach for the existence of pseudo almost periodic solutions for some second order differential equation with piecewise constant argument Original Research Article

The following equation d2/dt2(x(t)+px(t-1))=qx(2[(t+1)/2])+f(t)d2/dt2(x(t)+px(t-1))=qx(2[(t+1)/2])+f(t) is considered and necessary and sufficient conditions are given in order to ensure the existence and uniqueness of pseudo almost periodic solutions.