%N Degree of numerator and denominator of n-th order susceptibility series for 2-dimensional Ising model.
%D A. J. Guttmann and I. G. Enting, Solvability of some statistical mechanical systems, Phys. Rev. Lett., 76 (1996), 344-347.
%A _N. J. A. Sloane_, May 25 2000