Abstract
The non-convolution graphs, sometimes referred to as bridge graphs, which figure in the Mayer-Salpeter expansion of the potential of average forcew2(r) with respect to the plasma parameter, are systematically studied. They decrease at infinity faster than the first-order Debye graph e-r/r. An exact expression for w2(r) which allows a systematic improvement of the hyper-netted chain (HNC) approximation is obtained.