The expected duration of random sequential adsorption
  When gas molecules bind to a surface they may do so in such a way that the adsorption of one molecule inhibits the arrival of others. We consider random sequential adsorption in which the empty sites of a graph are irreversibly occupied in random order by a variety of types of ``particles.'' In a finite region the process terminates when no more particles can arrive. A universal asymptotic formula for the mean duration is given. 
Aidan Sudbury