Issue No. 02 - February (1978 vol. 27)
W.L.G. Koontz , Bell Laboratories
As Wetjen observed his comment, MN/M! is only an approximation to the number of ways N objects may be clustered into M nonempty classes. However, this formula has no bearing on our results?it is simply used to motivate the application of branch and bound.
W.L.G. Koontz, "Author's Reply<sup>2</sup>", IEEE Transactions on Computers, vol. 27, no. , pp. 189, February 1978, doi:10.1109/TC.1978.1675060