  Noether symmetry for Gauss-Bonnet-Dilatonic interaction exists for a constant
dilatonic scalar potential and a linear functional dependence of the coupling
parameter on the scalar field. The symmetry with the same form of the potential
and coupling parameter exists all in the vacuum, radiation and matter dominated
era. The late time acceleration is driven by the effective cos- mological
constant rather than the Gauss-Bonnet term, while the later compensates for the
large value of the effective cosmological constant giving a plausible answer to
the well-known coincidence problem.
