Horndeski theories self-tuning to a de Sitter vacuum
  We consider Horndeski cosmological models able to screen the vacuum energy
coming from any field theory assuming that after this screening the space
should be in a de Sitter vacuum with a particular value of the cosmological
constant specified by the theory of gravity itself. The most general
scalar-tensor cosmological models without higher than second order derivatives
in the field equations that have a spatially flat de Sitter critical point for
any kind of material content or vacuum energy are, therefore, presented. These
models could allow us to understand the current accelerated expansion of the
universe as the result of a dynamical evolution towards a de Sitter attractor.
