  Using a transfer matrix technique, we calculate the entropy of polydisperse
chains placed on a one-dimensional lattice, as a function of the density of
internal and endpoint monomers. The polydispersivity is determined considering
different activities for the two types of monomers, as is usual for
equailibrium polymerization and living polymers. If the mean number of monomers
in the chains is fixed, the entropy as a function of the density of monomers
displays a maximum and is limited from below by the entropy of monodisperse
chains. The increase of entropy due to the polydispersivity is a linear
function of the density of monomers. We also calculate the distribution of
chain sizes, obtaining an exponential relation.
