1D lattice dynamics of the diffusion limited reaction A+A->A+S:   Transient behavior
  We use a boolean cellular automaton model to describe the diffusion limited dynamics of the irreversible reaction A+A->A+S on a 1D lattice. We derive a set of equations for the dynamics of the empty interval probabilities from which explicit expressions for the particle concentration and the two-point correlation can be obtained. It is shown that the long time dynamics is in agreement with the off-lattice solution. The early time behavior, however, predicts a slower decay of the concentration. 
E. Abad, H.L. Frisch and G. Nicolis