I also thought about a sort of such example, but how you demonstrate the left part : 0 <= c*sin n<=3, let c=1. sin is a periodic function...which will be the n0, n>=n0 to satisfy the left inequality ?
I also thought about a sort of such example, but how you demonstrate the left part : 0 <= c*sin n<=3, let c=1. sin is a periodic function...which will be the n0, n>=n0 to satisfy the left inequality ?