Exact formulas for the buddy system

The statistical pairing of blocks of memory on the bottom level of the buddy system is studied. It is shown that the probability that k pairs of cells have one cell in use and that l pairs of cells have both cells in use is given by a rational function of @r, the ratio of the request rate for cells to the decay rate for cells in use. The values of the denominator, the leading and trailing coefficients of the numerator, and a common factor of the coefficients of the numerator are given.