Using the example of a disordered AyB1 –y solid solution in which the atoms occupy sites on a regular triangular lattice, it is demonstrated that the probabilities of the occurrence of many-particle configurations can be calculated analytically with allowance for pair correlations in the first coordination shell. An analytical solution is obtained by simultaneously taking into account the normalization conditions for the probabilities and maximizing the configurational entropy. Analogous individual solutions are also obtained for AyB1 –y solid solutions on square and face-centered cubic lattices. It is demonstrated that pair correlations in the first coordination shell on cubic and fcc lattices give rise to pair correlations of opposite sign in the second coordination shell.