Breather solutions of the discrete nonlinear Schrödinger equations with sign changing nonlinearitya) J. Math. Phys. 52, 043516 (2011); 10.1063/1.3580561 Breather solutions of the discrete nonlinear Schrödinger equations with unbounded potentialsIn this paper, we obtain infinitely many geometrically distinct solutions with exponential decay at infinity of the discrete periodic nonlinear Schrödinger equation Lu n − ωu n = ϱg n (u n ), n ∈ Z, where ω belongs to a spectral gap of the linear operator L, ϱ = ±1, and the potential g n (s) is symmetric in s, asymptotically or super linear with more general hypotheses as |s| → ∞ for all n ∈ Z. Our arguments are based on some abstract critical point theorems about strongly indefinite functional developed recently. C 2015 AIP Publishing LLC. [http://dx.