Cold dark matter dominated, inflationary universe with Omega(0) less than 1 and N less than 1

The theoretical prejudice for a flat universe with an initially scale- invariant power spectrum has restricted the number of cosmological scenarios investigated for studying the formation of structure in the universe. We consider a cold dark matter dominated universe with a density parameter {OMEGA}_0_ and a primordial spectral index n different from unity and discuss its possible consistency with the inflationary model. We show that some of the difficulties of a flat cold dark matter scenario can be avoided by having {OMEGA}_0_ < 1 and n < 1. For {OMEGA}_0_ ~ 0.4 and n ~ 0.75 we get a good agreement with the large-scale drifts, the bounds on the cosmic microwave background smoothness, the Abell cluster abundance, and their correlation function.