Long-distance contributions to the QCD pressure

The QCD pressure is a most fundamental quantity, for which lattice data is available up to a few times the critical temperature T,. Perturbation theory, even at very high temperatures, has serious convergence problems. Combining analytical and 3d numerical methods, we show that it is possible to compute the QCD pressure from about 2T(c) to infinity. We also describe an algorithm to generate and classify high order Feynman diagrams which is tailored to minimize computational effort.