The relationship of the correlation functions of the distribution func
tion of liquids to the nonlinearity parameter B/A is investigated. The
nonlinearity parameter is plotted as a function of the temperature an
d density for the potential of a system of hard spheres and the Lennar
d-Jones potential on the basis of data from a numerical experiment and
results obtained from the Percus-Yevick and Martynov-Sarkisov integra
l equations in the theory of liquids.