 show that, when "n" is a regular number and is divisible by 8, the generating function of an "n"-dimensional extremal even unimodular lattice is an "n"th power of a polynomial.As with other classes of smooth numbers, regular numbers are important as problem sizes in computer programs for performing the fast Fourier transform, a technique for analyzing the dominant frequencies of signals in time-varying data.For instance, the method of requires that the transform length be a regular number.