  We study the first 100Myr of the evolution of isolated star clusters
initially containing 144179 stars, including 13107 (10%) primordial hard
binaries. Our calculations include the effects of both stellar and binary
evolution. Gravitational interactions among the stars are computed by direct
N-body integration using high precision GRAPE-6 hardware. The evolution of the
core radii and central concentrations of our simulated clusters are compared
with the observed sample of young (about 100Myr) star clusters in the large
Magellanic cloud. Even though our simulations start with a rich population of
primordial binaries, core collapse during the early phase of the cluster
evolution is not prevented. Throughout the simulations, the fraction of
binaries remains roughly constant (about 10%). Due to the effects of mass
segregation the mass function of intermediate-mass main-sequence stars becomes
as flat as $\alpha=-1.8$ in the central part of the cluster (where the initial
Salpeter mass function had $\alpha=-2.35$). About 6--12% of the neutron stars
were retained in our simulations; the fraction of retained black holes is
40--70%. In each simulation about three neutron stars become members of close
binaries with a main-sequence companion. Such a binary will eventually become
an x-ray binary, when the main-sequence star starts to fill its Roche lobe.
Black holes are found more frequently in binaries; in each simulated cluster we
find about 11 potential x-ray binaries containing a black hole. Abstract
abbreviated....
