2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/68704We consider a sequences of symplectic twist maps corresponding to Frenkel Kontorova variational functional. For such a sequence without conjugate points we construct an invariant Lagrangian subbundle. Using the ideas by E.Hopf from Riemannian geometry we show that absence of conjugate points is a rare property for this class of maps.12 pages with no fguresSymplectic GeometryDynamical Systems37J35;3760;53D25text