We prove the existence of a pair of positive T-periodic solutions as well as the existence of positive subharmonic solutions of any order and the presence of chaotic-like dynamics for the scalar second order ODEu″+aλ,μ(t)g(u)=0, where g(x) is a positive function on R+, superlinear at zero and sublinear at infinity, and aλ,μ(t) is a T-periodic and sign indefinite weight of the form λa+(t)−μa−(t), with λ,μ>0 and large.

%B Journal of Differential Equations %V 252 %P 2922 - 2950 %G eng %U http://www.sciencedirect.com/science/article/pii/S0022039611003883 %R https://doi.org/10.1016/j.jde.2011.09.010