🚀 go-pugleaf

hello there,
i'm looking for an evaluation of cluster-integrals. i need it for the
partition-function of a real gas in the mayer-cluster-expansion.

i know that there must be an explicit formula for at least the 
first 4 cluster-integrals. the first 3 ones are

 b  = 1
  1

          infinity
     2*Pi  /                    2
 b = ----  | ((exp(-V(r)/kT)-1)r  dr
  2  L^3   /
           0

                infinity
       2     1   /  3    3
 b = 2b  +  ---- | d r  d r   f  f  f
  3    2    6L^6 /    12   13  12 13 23
                 0


L is the de broglie-wavelength and f   are the [ik] clusters of the molecules
                                    ik

there must be a phd-thesis by harrison: john hopkins-university 1938 on that
subject whee the first 4 clusterintegrals are computed. who knows something
about this subject?



thanks for your help    markus