... valid for functional differential equations in general form and for some cases of unbounded right-hand side of the equation see 1, Remark and , 2, Remark and In 1998, Stanˇ k worked on the existence ... results for second order nonlinear problems with maximum and minimum, ” e Mathematische Nachrichten, vol 192, no 1, pp 225–237, 1998 S Stanˇ k, “Multiplicity results for functional boundary value problems, ” ... 2 Advances in Difference Equations In this paper, we discuss the nonlinear second-order discrete problems with minimum and maximum: Δ2 u k − f k, u k , Δu k , u k : k ∈ T k ∈ T, max u k :...