  In the usual matrix-model approach to random discretized two-dimensional
manifolds, one introduces n Ising spins on each cell, i.e. a discrete version
of 2D quantum gravity coupled to matter with a central charge n/2. The
matrix-model consists then of an integral over $2^{n}$ matrices, which we are
unable to solve for $n>1$. However for a fixed genus we can expand in the
cosmological constant g for arbitrary values of n, and a simple minded analysis
of the series yields for n=0,1 and 2 the expected results for the exponent
$\gamma_{string}$ with an amazing precision given the small number of terms
that we considered. We then proceed to larger values of n. Simple tests of
universality are successfully applied; for instance we obtain the same
exponents for n=3 or for one Ising model coupled to a one dimensional target
space. The calculations are easily extended to states Potts models, through an
integration over $q^{n}$ matrices. We see no sign of the tachyonic instability
of the theory, but we have only considered genus zero at this stage.
