HOW TO COMPUTE ONE-LOOP FEYNMAN DIAGRAMS IN LATTICE QCD WITH WILSON FERMIONS

We describe an algebraic algorithm which allows to express every one-l oop lattice integral with gluon or Wilson-fermion propagators in terms of a small number of basic constants which can be computed with arbit rary high precision. Although the presentation is restricted to four d imensions the technique can be generalized to every space dimension. W e also give a method to express the lattice free propagator for Wilson fermions in coordinate space as a linear function of its values in ei ght points near the origin. This is an essential step in order to appl y the recent methods of Luscher and Weisz to higher-loop integrals wit h fermions.